After reading many of the same questions being asked I thought it would be a good idea to have one main thread that discusses the main ideas of a constant height setup.

This article will deal with constant height info.

Feel free to add anything I missed as I'll keep updating this main post.

WHAT IS IT?

What is a 2.35 Constant Height Setup?

In basic terms, its the ability to watch 2.35 material in full resolution and with full width just as the director intended. In a constant height setup 2.35 movies take up the whole screen without any black bars above/below. This a good read to get a better idea of constant height: http://resmagonline.com/articles/publish/article_774.shtml

What benefit does constant height provide over a normal 16x9 setup?

Because you are using the projectors full panel to display the 2.35 image, there is a 33% increase in resolution. The light output is also about 20% more than the same size picture without an anamorphic lens.

This results in a smoother more film like image that has alot more depth and punch to it.

Some other benefits of constant height also include more immersion for 2.35 films due to the extra width and no more annoying black bars. And also easier masking options.

HOW?

How does it work?

http://www.avsforum.com/avs-vb/showthread.php?t=830657

This link shows in a visual sense how a 2.35 constant height setup operates:
http://www.prismasonic.com/english/intro.shtml#2

http://www.panamorph.com/index.html See "How it Works" Box

WHAT DO I NEED?

What equipment do I need to run a constant height setup?

Here's a link that has some of the products that can be used for constant height: http://www.avsforum.com/avs-vb/showthread.php?t=537491

1. 2.35 programming

Movies/tv shows/dvd's and even trailers. Anamorphic enhancement preferred. Look out for HD 2.35 clips/movies in the future.

2. A 16x9 native projector

Although using a 16x9 projector with a lens is the ideal method for optimal resolution, it is just as possible to establish a constant height arrangement with just a 16:9 projector and no anamorphic lens and zooming (or a 4:3 projector with anamorphic lens and zoom) so long as you are comfortable with not using all of the projector's available pixels/brightness.

Projector/Lens Compatibility (http://www.panamorph.com/Compatibility.html)

3. Scaler that performs the required vertical stretch

This can either be built into the projector, dvd player, standalone scaler units or HT/Media Centre PC's. All you're after is the pre-lens vertically stretched image. Note though, that alot of projectors limit the options for changing the aspect especially when inputting upscaled DVD images.

Standalone scalers and HTPC's will generally provide more flexibilty.

4. 2.35:1 Screen

This means the screen is 2.35 units wide for every 1 unit high. Normal 16x9 screens are 1.78:1 ratio.

Most of the screen manufactures can produce a 2.35 ratio screen. DIY options are also possible. Again, all you're after is the 2.35:1 ratio.

The optimal screen for the true cinematic experience would be an acoustic sound screen that's transparent. This allows all front three speakers to be placed behind the screen with sound coming directly from the screen. Again, most manufactures provide this option. DIY solutions also exist, with Dazian Celtic Cloth and SMX (SandmanX) 720 being the most popular.

5. Anamorphic lens (Horizontal stretch or Vertical squeeze)

There are two ways to reach the final goal of constant height - Horizontal stretch lens or Vertical squeeze

Some may want to remove the lens for movies with ARs less than 2.35 in order to maximize the number of display pixels used. In so doing, there are a few things to bear in mind.

A situation occurs when removing a vertical squeeze lens that does not happen when removing a horizontal stretch lens. The displayed picture becomes too tall for the screen. That is assuming the screen AR matched that of the PJ and lens system. In that case the PJ zoom function must be employed to shrink the displayed pictured -- Hmm, scaling with a lens again. This time however the shrink occurs equally in both dimensions - isotropic scaling. The Pj would have to be capable of a zoom ratio of at least 1.322 : 1 , assuming the lens had a compress ratio of (16/9) / 2.35

A way of thinking about this is that the vertical squeeze lens does not affect the throw distance whereas a horizontal stretch lens decreases the throw.

Additionally, depending on the specific lens (either type) and projector, lens offset can enter into the mix and require additional adjustments. Some anamorphic lenses shift the position of the displayed picture vertically.

And finally, some projectors may shift the vertical position of the center of the picture when zoom is invoked as well.

Which Anamorphic lens is right for me?

http://www.avsforum.com/avs-vb/showthread.php?t=406915&page=1&pp=20&highlight=Anamorphic

http://www.prismasonic.com/english/specs.shtml Horizontal/ Vertical with option of motorized
http://www.panamorph.com/Products.html Vertical or Horizontal
http://www.isco.eu/index.php?id=home-cinema High end lens with option of motorized
www.cineslide.com Manufacturer of Isco lens transports, USA distributor for ISCO lenses

How Anamorphic lens technology works

How the different lenses work (http://www.avsforum.com/avs-vb/showthread.php?t=830657)

http://www.panamorph.com/Technology.html

SCREEN MASKING?

Manufacturers that sell Screen Masking for 2.35 (http://www.avsforum.com/avs-vb/showthread.php?p=8075863#post8075863)

What happens to sides of the 2.35 screen when I watch movies with less width (1.78/1.85 etc)?

You mask/cover up the sides of the 2.35 screen when you watch movies that aren't as wide as 2.35. Just like the real cinemas. Ever wondered why the movie screen widens for some films when you go the cinemas. Now you know. To maintain the height necessary for 2.35 movies the width must increase. Hence the term constant height.

A fellow member posted this:

"As with any fixed pixel display, when you need to map a non-native aspect ratio into the panel you will not use all of the pixels. Since the lens in this case transforms the 16:9 projector into a 2.35 projector any ratio other than this will result in either pillar boxing or letter boxing. For ratios greater than 2.35 this would be letter boxing (constant width). And of course this means anything less than 2.35 would have black bars on the sides, which is constant height"

How do I figure out how much I need to cover up?

The great thing about constant height is you only need to mask the sides of the picture. To figure out how much you need to mask when you watch movies with less width than 2.35 you multiply the screen height (which remains the same for all movies aka constant height), by the aspect ratio of the movie.

So say you watch a 1.78:1 ratio movie. For a screen 50" high you multiply it by 1.78. Hence the 1.78 units wide for every 1 high.

So 1.78 x 50" = 89"
1.85 x 50" = 92.5"
1.33 x 50" = 66.5"

As you can see a 1.78 movie is 89" wide out of the possible 117.5" for 2.35 movies. 2.35 movies of course don't need masking as they take up the whole width.

A very limited number of films are shot in ratios wider than 2.35 eg. Ben Hur. You can either live with the small black bars top and bottom, stretch the image so it fills the 2.35 screen or if you're totally obsessed mask the top and bottom. This would mean you would need a 4 way masking system.

What do I do with the anamorphic lens when I want to watch non 2.35 (scope)films?

There are a few ways to go about this.

1. Leave the lens in place all the time for all aspect ratios. This implies a loss in resolution and brightness for anything other than 2.35 films as the sides of the picture are now wasted on black pillar bars. A few on this forum leave the lens in place and don't notice any PQ loss as full vertical resolution is still used for all ratios.

One thing to take note of though with brightness is that because the 16x9 image is smaller in area to the 2.35 image, it requires less light to appear as bright as the 2.35 image. Therefore leaving the lens in place means that the brightness should be perceivable the same between 2.35 and 16x9.

The brightness drop occurs if you compared a 1000 lumen 16x9 image with no lens compared to a 500 lumen image with the lens. The areas are the same but the 1000 lumens is brighter as more light is covering that area.

So by keeping the lens in place you shouldn't notice difference in brightness between a full width 2.35 image and a 16x9 image with black bars on the sides.

2. Slide the lens out of place for non 2.35 movies. This uses full resolution/brightness for all aspect ratios. This can sometimes cause the picture to drop depending on the lens.

3. Leave the lens in place but use the passthrough mode that some lenses have (prismasonic range). This involves leaving the lens in place like option 1 but using the passthrough mode on the lens which means not stretching it horizontally and just letting the projected light 'passthrough' the lens unaltered. This like option 2 uses full resolution/brightness for all aspect ratios (2.35/16x9).

How a passthrough lens works.

http://gallery.avsforum.com/data/509/2new_housing.jpg

WHAT ABOUT CONSTANT WIDTH/AREA?

Constant Width is for those who can only accommodate a 16x9 screen. The width remains the same but the height changes. It still uses the full panel of the projector for 2.35 films but you dont get the extra width benefits for scope films. Only a vertical squeeze lens works for this application as you take the vertical stretched 2.35 picture and squeeze it down vertically to correct the geometry.

To find out more check out 'The 16:9 Screen Option' a little down the page: http://panamorph.com/Ultimate235.html

What about this Constant Area methology that everyone's talking about?

The idea behind Constant Area is that every aspect ratio has same/similar area. This means that every aspect ratio appears large as the brain perceives size in how much area an object has not in width or height. The screen ratio for constant area is 2.05 which is halfway between 1.78 and 2.35.

Here's some links that go into more detail:

http://archive.avsforum.com/avs-vb/showthread.php?s=&threadid=15649
http://www.videophile.info/Screen/Page_01.htm
http://www.mindspring.com/~zyber/cinema-screen.html


Where can I see some 2.35 Constant Height setups in action?

2.35 Picture Thread (http://www.avsforum.com/avs-vb/showthread.php?t=561280)
Jeff Leonard (http://gallery.avsforum.com/showgallery.php?cat=500&ppuser=58736)
Willy Gib (http://gallery.avsforum.com/showgallery.php/cat/500/ppuser/7485993)
Alan Gouger (http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=464220&highlight=electric+masking)
Gary Lightfoot (http://uk.geocities.com/g.lightfoot@btinternet.com/scope.html?)

Additional reading:

http://www.brooklyncenter.com/cinema/scope/articles/about_cinemascope.htm
http://www.thecinemalaser.com/anamorphic-enhancement-support-page.htm
http://www.thedigitalbits.com/articles/anamorphic/index.html
http://www.thedigitalbits.com/articles/anamorphic/aspectratios/widescreenorama.html
http://www.avsforum.com/avs-vb/attachment.php?attachmentid=39384

If I've missed anything please tell me and I'll add it on.

If I've missed anything please tell me and I'll add it on.

The thing that wasn't quite obvious to me at first was the "scaler" part.

As I understand it you can scale/stretch using 1) a DVD player, 2) a separate box between DVD player/projector, or 3) the projector.

I think the Panasonic PT-AE700 will do the vertical stretching, but I'm not sure if that's the best way to do it (certainly the cheapest). It might be nice to have
someone expand on this part.

Thanks for writing this up.

--Joachim

As I understand it you can scale/stretch using 1) a DVD player, 2) a separate box between DVD player/projector, or 3) the projector.

Yes that sounds correct.

I think the Panasonic PT-AE700 will do the vertical stretching, but I'm not sure if that's the best way to do it (certainly the cheapest). It might be nice to have
someone expand on this part.

Yes the AE700 will do the required vertical stretch. There's only a handful of projectors that will do this.

Yes the AE700 will do the required vertical stretch. There's only a handful of projectors that will do this.

This is only true of 480 source. Wish it were otherwise.

Good work BTW. :cool:
ted

Yeah true, upscaled I dont think works.

The only issue I have with the FAQ is that it implies that the only way to do constant height is with a 16:9 projector and anamorphic lens. Although this is the ideal method for optimal resolution, it is just as possible to establish a constant height arrangement with just a 16:9 projector and no anamorphic lens (or a 4:3 projector with anamorphic lens) so long as you are comfortable with not using all of the projector's available pixels.

Tukkis, while this covers more than constant height 2.35, we've had a lot of folks comment over the years that it has been helpful.

http://www.panamorph.com/ConfigurationGuide.htm

The only issue I have with the FAQ is that it implies that the only way to do constant height is with a 16:9 projector and anamorphic lens. Although this is the ideal method for optimal resolution, it is just as possible to establish a constant height arrangement with just a 16:9 projector and no anamorphic lens (or a 4:3 projector with anamorphic lens) so long as you are comfortable with not using all of the projector's available pixels.

This is very true. I'll add that comment to the post. The point of the FAQ was to answer some of the basics of constant height for new comers. Alot of the same questions kept popping up in this forum.

Tukkis, while this covers more than constant height 2.35, we've had a lot of folks comment over the years that it has been helpful.

http://www.panamorph.com/ConfigurationGuide.htm


Thanks Shawn, I added that link to the top.

Any thoughts about adding some info for those doing contant area set-ups, or is that a whole different can of worms?

Any thoughts about adding some info for those doing contant area set-ups, or is that a whole different can of worms?

I'd love to add it but dont know enough about the mechnics of it. If you or someone else would like to write a summary about constant area please do so and I'll add it in.

This is the only info I have about it. http://www.videophile.info/Screen/Page_01.htm

I have some screenshots from my constant-area setup here:

http://www.mindspring.com/~zyber/cinema-screen.html

If I find some free time, I'll write up a more detailed explanation of it.

Try this
http://archive.avsforum.com/avs-vb/showthread.php?s=&threadid=15649


ted

Ted and Josh, thanks I added those links in. I'll keep adding to constant area as I get more info.

Alternatively to step 4, one can use a vertical anamorphic lens that squeezes the picture back down therefore gaining the same benefits. Yes
If you were to use a vertical lens then you would have to manually zoom the projector the extra width necessary for constant height. This is a bit misleading. There is no "extra width necessary" for constant height. There may however be a width that you want for your setup.

The vertical lens can be put in front of a 16:9 projector and boom - it is 2.35. Since the width in that case stays the same, one way of thinking of it is that the throw distance is unchanged. That is in contrast to the horizontal stretch anamorphic lens which decreases the throw distance.
Without performing this zoom on a vertical lens it would only be a constant width, variable height setup and not constant height, variable width.
Other than changing the aspect ratio, the lens by itself does not make a PJ constant anything, nor does a one time zoom. The scaling performed prior to allowing the image to be displayed provides for the constancy element.

I realize that some will use the lens some of the time and remove it (or pass through) at other times. This then becomes another element of the "scaling" and typically allows for maximizing panel utilization albeit with a fluctuating illuminance ( which may or may not be a problem).

So the lens, either vertical of horizontal, merely changes the aspect ratio of the projector. As always, any picture aspect ratio greater than that of the PJ will result in a letterbox and anything less results in a pillar box.

jamin , thanks for the input. I updated that section with your feedback. Please check to see if its correct now.

Tukkis,

Hmm, let me try it this way.

The aspect ratio of the projector combined with the anamorphic lens transformation creates a new "native" aspect ratio for the projection system. It matters not whether the lens does a vertical squeeze or a horizontal stretch.

With respect to the aspect ratio, and given the same scalar, you can mutiply the numerator or divide the denominator and it makes no difference:

AR = ( 16 * k ) / 9 = 16 / ( 9 / k )

Any time the picture to be displayed is not the "native" aspect ratio of the projection "system" then the full panel will not be utilized.

This is true regardless of the type of lens used for the anamorphic transformation.

When the aspect ratio of the picture to be displayed is greater than that of the projection system then letter boxing needs to be established. Likewise if the AR of the picture to be displayed is less than that of the projection system then pillar boxing needs to be established.

Again this is true regardless of the type of lens used for the anamorphic transformation.

The panel AR of the projector should be thought of as a non square pixel panel that has the AR of the projection system when the lens is in place.

This is Irrespective of the type of lens employed.

If the lens is removed, or passed through, the PJ panel AR again becomes the aspect ratio that is native to the projector.

Scaling to the PJ panel is the same when either lens type is in place. Scaling to the PJ panel is the same when either lens type is removed.

****************************

A situation occurs when removing a vertical squeeze lens that does not happen when removing a horizontal squeeze lens. The displayed picture becomes too tall for the screen. That is assuming the screen AR matched that of the PJ and lens system. In that case the PJ zoom function must be employed to shrink the displayed pictured -- Hmm, scaling with a lens again. This time however the shrink occurs equally in both dimensions - isotropic scaling.

Additionally, depending on the specific lens and projector, lens offset can enter into the mix and require additional adjustments. Some vertical squeeze lenses shift the position of the displayed picture vertically. Some projectors may shift the vertical position of the center of the picture when zoom is invoked as well.

Tukkis,

Hmm, let me try it this way.

The aspect ratio of the projector combined with the anamorphic lens transformation creates a new "native" aspect ratio for the projection system. It matters not whether the lens does a vertical squeeze or a horizontal stretch.

With respect to the aspect ratio, and given the same scalar, you can mutiply the numerator or divide the denominator and it makes no difference:

AR = ( 16 * k ) / 9 = 16 / ( 9 / k )

Any time the picture to be displayed is not the "native" aspect ratio of the projection "system" then the full panel will not be utilized.

This is true regardless of the type of lens used for the anamorphic transformation.

When the aspect ratio of the picture to be displayed is greater than that of the projection system then letter boxing needs to be established. Likewise if the AR of the picture to be displayed is less than that of the projection system then pillar boxing needs to be established.

Again this is true regardless of the type of lens used for the anamorphic transformation.

The panel AR of the projector should be thought of as a non square pixel panel that has the AR of the projection system when the lens is in place.

This is Irrespective of the type of lens employed.

If the lens is removed, or passed through, the PJ panel AR again becomes the aspect ratio that is native to the projector.

Scaling to the PJ panel is the same when either lens type is in place. Scaling to the PJ panel is the same when either lens type is removed.


As I understand it when you put a anamorphic lens in front of a 16x9 projector, the projector is now a 2.35 projector. So as you said anything smaller than the projector ratio (2.35 with lens on) has black bars. With a horizontal and vertical lens this occurs. The way around it with a horizontal lens is passthrough or remove the lens. This inturn now makes it a 16x9 native projector. Removing the vertical lens also makes it a 16x9 projector again but as you said it's too tall. So zooming is required.

So the best and simplest way to get full resolution for 16x9 and 2.35 is use a horizontal lens. This means passthrough can be used and no zooming is required.

But you're right, both vertical and horizontal will work. Vertical just needs more effort to setup each time if you want the best PQ for all ratios.

Did I write anything incorrect in the faq?

Alternatively to step 4, one can use a vertical anamorphic lens that squeezes the picture back down therefore gaining the same benefits. CorrectIf you were to use a vertical lens and wanted to maintain constant height, you would have to scale or zoom anything narrower than 2.35 so that it fits within the height restrictions.If you want constant height then you need do nothing with AR less than 2.35 as long as the lens stays on -- regardless of which type of lens it is. This means anything less than 2.35 would have black bars on the sides if you use a scaler.This is true of either type of lens. If you zoom down then full picture quality is maintained for all ratios.The full panel resolution can only be utilized for 2.35 when the lens is on (either lens type) or for 16:9 movies when the lens is off. All other ARs decrease panel utilization. Of course this is always true of all projectors at any AR other than native.
You cant use all the projector's resolution/brightness for movies narrower than 2.35 with a vertical lens and still maintain constant height if you use a scaler.You can maintain constant height for ARs less than or equal to 2.35 with a scaler regardless of which lens type is in place. You can not use the full panel resolution for all aspect ratios as noted above, regardless of which lens type. If you leave the vertical lens in place and scale instead of zooming narrower films, you lose some resolution/brightness due to side black bars.And this is true whether the lens is a vertical squeeze or horizontal stretch.

Some may find this useful even in the CH forum.

Attached is a graph showing pixels on screen vs aspect ratio for various PJ configurations.

A couple of things to note : positive slope lines denote constant height (CH) regions and negative slope denotes constant width (CW) regions. The horizontal no slope lines are for constant area (CA) implementations.

EDIT:update jpg

Jamin, Thanks for the link. I added it to the post.

With regards vertical lens stuff we were discussing, would you mind writing a couple of paragraphs and I replace mine with what you write. This should clear alot of it up.

So the best and simplest way to get full resolution for 16x9 and 2.35 is use a horizontal lens. This means passthrough can be used and no zooming is required.

But you're right, both vertical and horizontal will work. Vertical just needs more effort to setup each time if you want the best PQ for all ratios.

Hi Tukkis. I would just like to add that it might be good to qualify this with a "for constant height". I realize this is a constant height forum but a constant width forum does not exist here at this point. Vertical compression lenses are best for max resolution in a constant width scenario.

Also note that some horizontal lenses still produce a vertical offset when they are removed, so the relative ease of achieving 16:9 max res even in CH mode depends on the horizontal lens type.

With regards vertical lens stuff we were discussing, would you mind writing a couple of paragraphs and I replace mine with what you write. This should clear alot of it up.
1. ~~~~~
2.~~~~~
3.~~~~~
4. An Anamorphic lens (Horizontal stretch or Vertical squeeze)
5.~~~~~

As with any fixed pixel display, when you need to map a non-native aspect ratio into the panel you will not use all of the pixels. Since the lens in this case transforms the 16:9 projector into a 2.35 projector any ratio other than this will result in either pillar boxing or letter boxing. For ratios greater than 2.35 this would be letter boxing (constant width). And of course this means anything less than 2.35 would have black bars on the sides, which is constant height

Some may want to remove the lens for movies with ARs less than 2.35 in order to maximize the number of display pixels used. In so doing, there are a few things to bear in mind.

A situation occurs when removing a vertical squeeze lens that does not happen when removing a horizontal stretch lens. The displayed picture becomes too tall for the screen. That is assuming the screen AR matched that of the PJ and lens system. In that case the PJ zoom function must be employed to shrink the displayed pictured -- Hmm, scaling with a lens again. This time however the shrink occurs equally in both dimensions - isotropic scaling. The Pj would have to be capable of a zoom ratio of at least 1.322 : 1 , assuming the lens had a compress ratio of (16/9) / 2.35

A way of thinking about this is that the vertical squeeze lens does not affect the throw distance whereas a horizontal stretch lens decreases the throw.

Additionally, depending on the specific lens (either type) and projector, lens offset can enter into the mix and require additional adjustments. Some anamorphic lenses shift the position of the displayed picture vertically.

And finally, some projectors may shift the vertical position of the center of the picture when zoom is invoked as well.

************************************************

Thanks jamin, I replaced mine with what you wrote.

Great and noble effort Tukkis!
Here's some outstanding issues I'm having during my CIH design (Infocus 7210 / Primasonic H-1000 / Premiere Gyrolock):

1) Lumen calculations: What percentage loss/gain between a 16:9 letterboxed image and the full panel / 2.35:1 stretched image?

2) Mounting the lens. Does it have to be DIY? Do any ceiling mounts have extensions?

3) Should screen to seating ratios change based on new stretched pixel size? (Not that I'd move my sofa back and forth mind you ;)). 4/3x is standard with 720p. Should that be reconsidered?

1) Lumen calculations: What percentage loss/gain between a 16:9 letterboxed image and the full panel / 2.35:1 stretched image?


About a 20% increase between a zoom/letterboxed 2.35 image and one with the lens that uses the full panel.

2) Mounting the lens. Does it have to be DIY? Do any ceiling mounts have extensions?


There may be. I dont know enough about that to give you a decent answer. Maybe do a search on here to see how others mount theirs.

3) Should screen to seating ratios change based on new stretched pixel size? (Not that I'd move my sofa back and forth mind you ). 4/3x is standard with 720p. Should that be reconsidered?


I dont have a constant height setup yet but from what I've read for seating distances, about 1.2-1.3x for 2.35 images were what most were using. Its up to personal preference really so maybe try it on the wall first to see the size. Or if you can move seating then you have a bit of leeway.

My 2.35 setup (http://gallery.avsforum.com/showgallery.php/cat/500/ppuser/7485993)

O NELLY!!! O WILLY!!! I am stunned. What an incredible job. Thank you so much for posting. It gives people like me so much hope and excitement waiting for my goodies to arrive so that I acn proudly join you guys. What scaler are you using? The H1000 gives a stunning picture. Enjoy.

O NELLY!!! O WILLY!!! I am stunned. What an incredible job. Thank you so much for posting. It gives people like me so much hope and excitement waiting for my goodies to arrive so that I acn proudly join you guys. What scaler are you using? The H1000 gives a stunning picture. Enjoy.

The 4805 has a letter box mode that will do the vertical stretch for 2.35 films, so for now thats what I use. Once I upgrade the PJ, in a couple of years, then I will think about a scaler (Dragonfly) :D

Just a quick post to say you can check out my 2.35 setup here in the member's gallery.

Excellent work, Jeff. When am I going to be able to watch my movies in 2.35:1 ?

Thanks for those links. I added a section to the original post with links to user setups.

Got my 2.35:1-love busted up some today. I just found out that switching between passthru and stretch mode on the Prismasonic requires refocusing the projector lens. What's the point of upgrading to the motorized option if I still need to jump up and realign my 7210 focus ring? Maybe this is ideal for a pj (like the H79) which also has a motorized focus ring. It probably won't be a big deal, but it still comes as a shock. There goes the automation. :(

Got my 2.35:1-love busted up some today. I just found out that switching between passthru and stretch mode on the Prismasonic requires refocusing the projector lens. What's the point of upgrading to the motorized option if I still need to jump up and realign my 7210 focus ring? Maybe this is ideal for a pj (like the H79) which also has a motorized focus ring. It probably won't be a big deal, but it still comes as a shock. There goes the automation. :(

can't you just leave it in place the whole time?

You mean leave it in stretch mode for non-2.35:1 material and then digitally recompress the image back to 16:9? Not an option I'd consider. It would interpolate/resample the image.

I appreciate the suggestion, but why even have a passthru mode in that case?

Got my 2.35:1-love busted up some today. I just found out that switching between passthru and stretch mode on the Prismasonic requires refocusing the projector lens. What's the point of upgrading to the motorized option if I still need to jump up and realign my 7210 focus ring? Maybe this is ideal for a pj (like the H79) which also has a motorized focus ring. It probably won't be a big deal, but it still comes as a shock. There goes the automation.

Thats not good news if its true. I'm seriously looking at Prismasonic and one of the major selling points is the passthrough mode. The whole convienience aspect goes out the window.

Can anyone confirm the refocus?

You mean leave it in stretch mode for non-2.35:1 material and then digitally recompress the image back to 16:9? Not an option I'd consider. It would interpolate/resample the image.

I appreciate the suggestion, but why even have a passthru mode in that case?

Exactly if you're going to keep it in place all the time the P752 lens will do great. Even though it's a vertical both do the same - make the projector into a 2.35 ratio one

You mean leave it in stretch mode for non-2.35:1 material and then digitally recompress the image back to 16:9? Not an option I'd consider. It would interpolate/resample the image.

I appreciate the suggestion, but why even have a passthru mode in that case?

I'm not familiar with Prismasonic products too well, but I know that you CAN do this with a Panamorph lens and TheaterTek, and the results are fantastic...

If you're working with any kind of decent video scaler (like TheaterTek and a HTPC) you will hardly notice a quality difference...

If you're working with any kind of decent video scaler (like TheaterTek and a HTPC) you will hardly notice a quality difference...

Joe, the resolution drop is ok cause there's heaps with most projectors anyway for dvd. Hows the brightness drop though? Is it noticeable?

I'm not familiar with Prismasonic products too well, but I know that you CAN do this with a Panamorph lens and TheaterTek, and the results are fantastic...

If you're working with any kind of decent video scaler (like TheaterTek and a HTPC) you will hardly notice a quality difference...

This is really putting me through the wringer. Maybe it's fortunate that the Primasonic is backordered. I have the 2.35:1 Stewart screen on the way so I am totally committed to CIH, but I do not want to refocus between 2.35:1 and 16:9 material.

Also, 16:9 HDTV cable is the only true HD source I (and most of us) have. Stretching to 2.35:1 and then compressing to 16:9 what would have been 1:1 material seems inelegant to me. You say the results are hardly noticeable, but it ought to be unnecessary.

Can anyone confirm the refocus?
Indeed.

Alan -- would you chime in here. Does the Prismasonic H series require projector refocusing after switching from passthru to stretch mode (or visa versa).

Without some sort of scaler, I don't see how it wouldn't require it.

This is what Prismasonic emailed me:
"No, it's not necessary if the lens will be front of the projector all the time."

This is what Alan Gouger PM'd me:
"If you focus to the 16x9 passthrough mode then stretch the lens to 235:1 you will be out of focus."

Does anyone have an authoritative, unambiguous answer to the question "Does switching from passthru to stretch mode (or from stretch to passthru mode) with a fixed-mounted Prismasonic H-1000 cause a change in focus." :confused: :D c'mon. There are lots of H-1000 owners out there.

I focus my 4805 in the pass-through mode. When I do the stretch for 2.35 I DO NOT refocus. The slight un-focus (if there is any) seems to help with the SDE with the 4805.. The problem with the 4805 is not the deference in focus from pass-through to stretch it's the lack of resolution, small objects and background objects are not crisp, but then again I'm pushing the 4805 past it's limits on a 128" screen. I can't tell the deference in focus from pass-through to stretch because of this, but I will tell you it still looks great. :D

I utilize the H1000 with a Panasonic AE 700 and I also confirm what others have, that I do not find it necessary to refocus in the stretch mode after having focused in passthrough.

ted

Thanks for the feedback guys! I've got a dealer (not AVS) telling me otherwise. So maybe he's got a defective unit. Or something.

Looks like I'll go ahead with the order ...

I am planning to use constant height screen for my new theater. Recently I saw Dennis Erskine`s theater in atlanta.He has a curved screen,looks cool...How do you set up a curved screen ,who makes it ,and how difficult it is to set one up?.Appreciate any help.

I was playing around with the focus on the 4805 with the H-1000 lense. First I made certain that the focus looked good in the pass-through mode, then checked it in the stretch mode. The focus was a little out. Then I re-focused in stretch mode and checked it in pass-through mode. What a surprise. It looked like the focus got better in pass-through. The focus seemed to be tighter. I don't know if this is a result of stretching the pixels and being able to see the focusing better, but it did look better doing the focus in the stretch mode first. :confused:

I was playing around with the focus on the 4805 with the H-1000 lense. First I made certain that the focus looked good in the pass-through mode, then checked it in the stretch mode. The focus was a little out. Then I re-focused in stretch mode and checked it in pass-through mode. What a surprise. It looked like the focus got better in pass-through. The focus seemed to be tighter. I don't know if this is a result of stretching the pixels and being able to see the focusing better, but it did look better doing the focus in the stretch mode first. :confused:
I may have that definitive answer I was looking for, and it ought to address what you've just described Willy.

This is from an email exchange between myself and Prismasonic:

> Why are these guys saying there's a focus change between passthru and stretch?

They are right. There is a little change in focus between the 'pass' and
'stretch' modes. However, the change is not visible, especially if one does the
focusing in the middle of the 'pass' and '2.35:1 stretch' modes. H-1000 allows
to do that because it is truly variable. Doing so there is no need to refocus
the projector manually, and thus it will be 100% automatic.

Makes sense. Willy: Can you try it? Focus in the middle of the 2 modes.

I may have that definitive answer I was looking for, and it ought to address what you've just described Willy.

This is from an email exchange between myself and Prismasonic:

> Why are these guys saying there's a focus change between passthru and stretch?

They are right. There is a little change in focus between the 'pass' and
'stretch' modes. However, the change is not visible, especially if one does the
focusing in the middle of the 'pass' and '2.35:1 stretch' modes. H-1000 allows
to do that because it is truly variable. Doing so there is no need to refocus
the projector manually, and thus it will be 100% automatic.

Makes sense. Willy: Can you try it? Focus in the middle of the 2 modes.

I'll give it a shot tonight, but I can hardly tell the difference now without a test pattern up if I do the focus in stretch mode.

Re focus is not needed with the Prismasonic. Perform initial projector & lens focus in the 235:1 mode. Once thats done you are all set. You will never have to focus again and focus will remain stable between 16x9 & 235:1

Is there any solution for the subtitle issue? The film to DVD transfer has it floating in the bottom black bar.

Ideally the HD-DVD/Blu-ray format includes character generation on the fly in the language and screen position of your choice. Fantasy?

Is there any solution for the subtitle issue? The film to DVD transfer has it floating in the bottom black bar.

I messaged Blight the developer of Zoom Player. He said, "As far as I know, microsoft didn't publish such an interface for DVDs". I told him that TheaterTek allows you to nudge the subtitle up/down. He then said, "They might be using their own subtitle renderer instead of the one provided by the video decoders. I'm going to ask around a bit, but no promises."

So hopefully fingers crossed we'll have an update for it in a future release.

Still totally confused..

Wouldn't it make sense that a dvd player crops the black bars of the signal, and stretch the height (making people very thin) - while a projector-lense could simply stretch it out (to the sides), making it thin, alternatively squish it heightwise?

Is there a dvd player/projector combo that can accomplish this without an additional lense?

Just FYI, I have the Zenith 318 dvd player. (No projector or screen yet, though I'm looking for a house with a fitting basement, where I can have a 2.35:1 setup..)

PS;I'm hoping for such a combo, because;
a) limited budget, probably 2000 USD, MAYBE 2500.. (projector, screen, and possibly lense???)

b) Ease of setup...I'm growing tired of spending a lot of time setting up things... I've done it in the past, but at this point, I am lazy..

Thanks.

Wouldn't it make sense that a dvd player crops the black bars of the signal, and stretch the height (making people very thin)

Ok so far...

- while a projector-lense could simply stretch it out (to the sides), making it thin, alternatively squish it heightwise?


The stretch thing sound like a horizontal expansion lens (prismasonic) , the "squish" sounds like a vertical compression lens (Panamorph).

Thanks Jack. After looking further, I take it no projector has a built in lens system that can do either, correct?

Also, it seemse given my budget, if I am to trust the projector to do the first piece, I have a limited number of choices :)

Thanks Jack. After looking further, I take it no projector has a built in lens system that can do either, correct?
None I've seen...anamorphic lenses are much larger than the zoom lenses you find on projectors. Some have been available with them (I recall an NEC), but not "built-in" per se.

Also, it seemse given my budget, if I am to trust the projector to do the first piece, I have a limited number of choices
'fraid so...although the 4805 fits that bill and I can heartily recommend it paired with a Panamorph 752...you'll come in well under budget even with a good screen.

http://www.avsforum.com/avs-vb/showthread.php?p=5967215&&#post5967215

Thanks. I pretty much figured the 4805 was the obvious choice at this point :)

Question though; Seems I could get a 720p native projector for less than 2K. In terms of resolution, even when losing the lines that are used for black bars, wouldn't the net result be pretty similar (480p vs 720p 'cropped' - for lack of a better term). Also, I would be prepared for HD dvd (depending on format/rez). On the downside, I guess the black bars would be projected, ruining some of the 'cinema' feel?

Question though; Seems I could get a 720p native projector for less than 2K. In terms of resolution, even when losing the lines that are used for black bars, wouldn't the net result be pretty similar (480p vs 720p 'cropped' - for lack of a better term). Also, I would be prepared for HD dvd (depending on format/rez). On the downside, I guess the black bars would be projected, ruining some of the 'cinema' feel?
All good points. You'd actually have a little more vertical resolution from "cropped" 720 than from squeezed 480p. I prefer the overall image (of which resolution is only a part) of the 4805 to the ~$2000 (implying LCD) 720p I've seen, but higher res is certainly in my future when there's stuff I want to watch (HD DVD). Of course, a lens like the 752 will have the same benefits with any digital pj...using the full panel resolution.

Resolution is part of the benefit of an anamorphic lens, but the other main benefit is having a "constant height" setup with a 2.35 screen. This is do-able without a lens in many setups, but requires more scaling/re-zooming.

Thanks, you are starting to convince me that yours is the way to go! I have about 500 dvds, and that will certainly be what i watch and aquire mostly for even the next few years!

How much do you think I would have to pay for the 752?

PS: Is the 4805 capable of outputting sufficient light onto a 9.4 feet wide screen? The room will be well controlled when it comes to lighting (basement). Not sure if any of you are familiar w/parkland, but I figure I would try tha as a diy solution first, for the screen,

Thanks again for all your helpful advice, Jack!

https://www.panamorph.com/P752Clearance.html


Not sure on the brightness. Try this calculator (http://www.projectorcentral.com/InFocus_Home-ScreenPlay_4805-projection-calculator-pro.htm) to get an idea, keeping in mind you want to shoot for 12 fL or so for theater-level brightness. The lens will add about 20% to this level. Brightness also diminishes as the bulb ages. At that width, I'd recommend you sit at least 14' back.

Thanks again for all your helpful advice, Jack!
Just passing on the help I recieved. :)

Try this calculator:

http://www.carltonbale.com/ht/calculator/index.html

It's way better as it has a 2.35 screen option plus a ton of other stuff.

Thanks guys, good link to the page for lenses, and the calculator is awesome!

-Tom

Very cool calculator! At my width and distance, I'm right between the THX and SMPTE viewing distances.

Please help me with the dumb question. I have a 16:9 (optoma H79) projector with a 16:9 screen. How could a lens help in improving the pics from a 2.35 source without distorting it? Meaning, can a lens be used to fill the whole screen without distortion? or I am pretty much struck with top and bottom bars?
Thanks,
Frank

If you use an IMX lens it might help but it will not get rid of the bars. With an anamorphic lens you can get rid of the bars with a 2.35 source but you will still need a 2.35 screen.

Tukkis, I hope you can help.

I have a Panny 500U, Bravo D2, Panamorph 752 lens. Besides the lens, can the PJ or player do a vertical stretch? The Bravo has a custom setting but I can't get it to work for what I'm looking for. Maybe you'd know. Do I add another device?

Anybody else can chime in.

Thanks

I was thinking I had heard others say the D2 will do vertical stretch of 2.35 material? On my Sanyo Z2 I found I can vertically stretch 480i or 480p signals, but as soon as I try 720p or 1080i over HDMI/DVI it won't work.

vitod, sorry I don't have any experience with the D2. If it has a custom setting you want a 4x3 (1.33333 etc) vertical stretch.

The panny probably wont do it. My ae700 wont do it for anything above 480 so it's no use. A standalone scaler will give you more flexibility with the inputs as well.

what's this?

Thanks for the info!

Hi kofboy:

What do you mean by "what's this"? Are you asking what 2.35 is all about? Are you asking about the lens required? Are you asking about a scaler? What do you need to know? Be more specific and you shall be enlightened.

1. Leave the lens in place all the time for all aspect ratios. This implies a loss in resolution and brightness for anything other than 2.35 films as the sides of the picture are now wasted on black pillar bars. A few on this forum leave the lens in place and dont notice any PQ loss as full vertical resolution is still used for all ratios.

True: However, the amount of light reflecting off the screen per unit area, FtL is the same if you leave the lens in place at all times.

Hello all, I have just installed a home made version (dual prism based) of an anamorphic lens.

I have been researching this for quite some time and now have successfully achieved a constant height set up that allows me to switch between 21:9 and 16:9 without having to remove the lens from the light path. My geometry is correct and I do not have annoying black bars at the top and bottom of "cinema scope" presentation...

http://www.avsforum.com/avs-vb/showthread.php?t=561280

Mark :)

Hello all, I have just installed a home made version (dual prism based) of an anamorphic lens.

I have been researching this for quite some time and now have successfully achieved a constant height set up that allows me to switch between 21:9 and 16:9 without having to remove the lens from the light path. My geometry is correct and I do not have annoying black bars at the top and bottom of "cinema scope" presentation...

Sorry for the noise in the images, but the borrowed camera was not the best...


Congrats on the setup. Looks good. With every ratio properly sized and masked properly it really adds to the cinema feel.

Thanks Tukkis,

Yes it does help make my system more cinematic...

Mark

I was thinking I had heard others say the D2 will do vertical stretch of 2.35 material? On my Sanyo Z2 I found I can vertically stretch 480i or 480p signals, but as soon as I try 720p or 1080i over HDMI/DVI it won't work.


So what is the alternative to this? I'll be purchasing the Z3 (as you already know SQ) and I know that it will also have the limitations with 720p and 1080i material as the Z2. In order to make the vertical stretch work with this do you need an external scaler like the Iscan or something similar?

It is my understanding that if you want to perform the vertical stretch on 720p or 1080i material via a Z2 or Z3, and many other projectors, you have to have HTPC, DVDO, or other scalers that perform this task. It is my understanding that some projectors will achieve this, like the Infocus models, but they are not cheap, at least the 720AR and above models.

Someone else please help this poor guy out :)

Well once again you've covered my a$$ SQ :o By the way thanks a MILLION for the info via PM, you're the $h** in my book. But the fun isnt over I still have a couple of questions for you, so keep an eye out for me. :cool:

1st Cav

I'm setting up my Projector and Screen today for constant height. Here's the big question. I have DVDs that are 1.78, 1.85, and 2.35. How do I ensure that none of the movies will have black bars on the top and bottom? Its a 16/9 projector so 1.78 will fill the panel with NO black bars, but 1.85 WILL have black bars right? Do I set it up so that 1.85 fills the screen (and the top/bottom black bars go onto the frame and 1.78 movies lose a little picture) or do I set it up so that 1.78 fills the screen and 1.85 will have slight black bars on top/bottom. Also which will translate better when I use the anamorphic lens to stretch 2.35 movies and not lose any top/bottom of pic? Thanks. I'm surprised I didn't see this question somewhere here in the FAQ already.

Until further notice I shall setup the screen using a 1.85 DVD...that way everything will have a very slight overscan except 1.85 DVDs, but there will be no black bars on top/bottom which sounds good to me. If anyone deals with this differently let me know.

Im using Optoma H77 for projecting and scaling and a Prismasonic H600m lens for the anamorphic stretch. (my DVD player is a Denon 3910, excellent in all regards except no scaling options).

FoolintheRain -
In order to have a true constant height system, you are right, one would have to have different amounts of scaling available for the different aspect ratios. Most here, it seems, just allow for the 16:9 to 2.35 jump. Some allowing the thin letter box bars to be visible for the 1.85 presentation or with perhaps a nod to the 1.85 by using the approximate 4% overscan on 16:9 that would eliminate those bars for the 1.85. That overscan also applies to the 2.35 as well.

Mostly it just depends on what equipment and $ you have available and what irks you the least.

Check out this link for some ideas: http://www.avsforum.com/avs-vb/showthread.php?p=5692017&&#post5692017

I don't remember seeing this link anywhere, just a simple explanation of anamorphic lenses that might help someone. It's old, dealing with 4:3-16:9 conversion.

http://www.projectorcentral.com/anamorphic_lenses.htm

By now you would think I shouldnt be asking this basic question but I still dont understand this. So here I go with the basic question.

Lets say I have a 16:9 projector like 4805 and I dont have any external scaler or DVD player that does the scaler.

Now I put a horizontal anamorphic lens.

Lets say the image I am feeding is already 16:9 so the PJ is using full panel.

Lets say the lens does not have a pass through model.

So the lens will stretch the 16:9 image and if the lens does not have the pass through mode the only option is to move it out of the way in which case the image will drop right? Am I missing anything here?

By now you would think I shouldnt be asking this basic question but I still dont understand this. So here I go with the basic question.

Lets say I have a 16:9 projector like 4805 and I dont have any external scaler or DVD player that does the scaler.

Now I put a horizontal anamorphic lens.

Lets say the image I am feeding is already 16:9 so the PJ is using full panel.

Lets say the lens does not have a pass through model.

So the lens will stretch the 16:9 image and if the lens does not have the pass through mode the only option is to move it out of the way in which case the image will drop right? Am I missing anything here?

Take a look at the official picture thread images of which my set up is now a part. http://www.avsforum.com/avs-vb/showthread.php?t=561280

EDIT: I have to this as the pictures previously being refered to have been removed.

When the photo was taken, I was having some alignment issues that have since been corrected, but you get the idea...

Mark

So the lens will stretch the 16:9 image and if the lens does not have the pass through mode the only option is to move it out of the way in which case the image will drop right?
If you can't scale the image to restore proper geometry, your option is to move the lens out of the way. For what it's worth, your 4805 example from above does not need an external scaler, as it does all the scaling needed to leave the lens in place for 1:85 films or HD. If a lens "stretches" the image (horizontal), it won't cause a drop, but will typically have a passthough mode. A vertical lens (squeeze)won't have such a mode and will cause a drop.

Now I put a horizontal anamorphic lens.

Lets say the image I am feeding is already 16:9 so the PJ is using full panel.

Lets say the lens does not have a pass through model.


Which horizontal lens are you looking at that doesn't have a passthough mode?

At the top of this FAQ, it states:
Because you are using the projectors full panel to display the 2.35 image, there is a 33% increase in resolution.
How is the 33% increase in resolution gained if the lens is simply expanding the same 16x9 image that the DVD player (thru a scaler) is sending out? Is there a special DVD player that you can configure to say "2.35 display" rather than "16x9" so that it actually sends out a full resolution image at 2.35 rather than a letter-boxed 16x9 image that must be scaled by an external scaler??

If not, then this setup IS NOT increasing the ACTUAL resolution ... it is simply relying on an external scaler to digitally expand the height so that the lens then stretches it. This actually means that the 2.35 movies ARE NOT even using the full resolution of DVD ... right? They are wasting a good portion of the resolution on those darn letterboxes.

When the DVD is encoded, is it encoded at the full 2.35 AR, or is it encoded at 16x9 with letterboxing in the encoded picture (thus NOT using the full resolution of DVD)?

Thanks for any details you can shed on this!

................ or is it encoded at 16x9 with letterboxing in the encoded picture (thus NOT using the full resolution of DVD)?
Bingo -- For anamorphic DVD , all is mapped to a 16:9 frame, so there is waste for anything bigger than 16:9

The "increase in resolution" pertains to utilization of more pixels on the display, which isn't a bad thing.

Just a shame, as has been commented for years, that the more epic the motion picture - the less pixesl are devoted to it. Likewise CH mavens are seeking to make the picture bigger with fewer pixels.

Typical "do more with less" motto .

Bingo -- For anamorphic DVD , all is mapped to a 16:9 frame, so there is waste for anything bigger than 16:9

The "increase in resolution" pertains to utilization of more pixels on the display, which isn't a bad thing.

Just a shame, as has been commented for years, that the more epic the motion picture - the less pixesl are devoted to it. Likewise CH mavens are seeking to make the picture bigger with fewer pixels.

Typical "do more with less" motto .

I have fairly entry level equipment, hence why I built my lens. Now that I have a 2.35:1 CIH set up, every thing runs at the max vertical rez. In my case it is just 854 x 480 but now both 16:9 and 21:9 run the same 480 vertical rez. Scaling is done by the projector and the images are much more dynamic than the previous letterboxed images. The larger image (2.35:1) is now larger, with as much detail and brightness as the smaller 1.78:1 image...

Mark

can't you just leave it in place the whole time?


Who ish dish? Get off my line! jett off, jett off NOW!!

Midway Sub-HOLD!
Hot or Cold the Midway???


Wally& OLGA SCHAFF

All your bases...

WOW interesting...and confusing thread. It is actually making me consider 2.35:1 for my dedicated theater.

I have a Sharp 10000 can I get an anamorphic lense for it?

Almost all of my DVDs are Anamorphic, do I still need the lense.

Sorry if these questions are very basic for this thread.

Dave

You still need the lens because the projector is native 16x9 (1.78) and you want to turn it into a 2.35 projector by adding the lens.

You should be looking at whether your dvd's are 1.78 or 2.35 aspect ratio not so much whether they are anamorphic or not.

I'm having the darndest time getting my retail 2.35 dvds to work on my 2.35 screen. I have the following:

Panny AE900U
2.35 Screen
UH-50 lens
Iodata Avel Link player 2.

Basically the problem is that i can not get my dvd player to stretch the 2.35 material vertically, thereby entirely removing the black bars before it gets to my projector. Is this how everyone else is doing it?

It seems like this needs to happen for it'll work? Please definately correct me if i'm wrong.

See if you can stretch it on the projector.

Hi,

my name is samy and I'm french (sorry for my english :o )
I Have created 2 topics on a french forum about 2.35 pojection and DIY anamorphic lens.

DIY LENS :
http://www.homecinema-fr.com/forum/....php?t=29803723

2.35 PROJECTION :
http://www.homecinema-fr.com/forum/....php?t=29801701

We create a group command for prisms in BK7, all specifications are on the forum. If you want to post in english, no pbl. :)

sam ;)

DIY ANAMORPHIC LENS OF GLUBUX, A FRIEND ;)

http://www.hiboox.com/vignettes/706/u3wtw3b.jpg http://www.hiboox.com/vignettes/706/t7kyt22.jpg http://www.hiboox.com/vignettes/706/ydhxh0z.jpg http://www.hiboox.com/vignettes/706/b0ve-la.jpg http://www.hiboox.com/vignettes/706/s2-uaf7.jpg http://www.hiboox.com/vignettes/706/ox1nylg.jpg

http://www.hiboox.com/vignettes/706/a3zyqoe.jpg http://www.hiboox.com/vignettes/706/0h2ges2.jpg http://www.hiboox.com/vignettes/706/rpnf9vt.jpg http://www.hiboox.com/vignettes/706/zkrriov.jpg http://www.hiboox.com/vignettes/706/noeav3x.jpg http://www.hiboox.com/vignettes/706/q4zwdog.jpg

http://www.hiboox.com/vignettes/706/osnwio4.jpg http://www.hiboox.com/vignettes/706/2vqy4lk.jpg http://www.hiboox.com/vignettes/706/954wquf.jpg http://www.hiboox.com/vignettes/706/ak7op84.jpg http://www.hiboox.com/vignettes/706/vm0w2ha.jpg http://www.hiboox.com/vignettes/706/niv-vbw.jpg

http://www.hiboox.com/vignettes/706/eal3cai.jpg http://www.hiboox.com/vignettes/706/jhknyys.jpg http://www.hiboox.com/vignettes/706/gb-3c5u.jpg http://www.hiboox.com/vignettes/706/d9qqvtb.jpg http://www.hiboox.com/vignettes/706/y7-54eh.jpg http://www.hiboox.com/vignettes/706/f20nxq-.jpg http://www.hiboox.com/vignettes/706/68wfyui.jpg http://www.hiboox.com/vignettes/706/11iz25g.jpg http://www.hiboox.com/vignettes/706/9u995o3.jpg http://www.hiboox.com/vignettes/706/b1zj8uu.jpg

I'm having the darndest time getting my retail 2.35 dvds to work on my 2.35 screen. I have the following:

Panny AE900U
2.35 Screen
UH-50 lens
Iodata Avel Link player 2.

Basically the problem is that i can not get my dvd player to stretch the 2.35 material vertically, thereby entirely removing the black bars before it gets to my projector. Is this how everyone else is doing it?

It seems like this needs to happen for it'll work? Please definately correct me if i'm wrong.
Jizzay are you connected with YPbPr or HDMI? (This might not work over digital).
1. Ensure the DVD player is set to 16:9.
2. Select the right input for your source.
3. Select the right AR using the remote. You should have different modes to choose from including 4 x 3, ZOOM and 16:9. You need the ZOOM mode which is a 4 x 3 mode that fills the entire width of the panel. The image should look like this.
http://i49.photobucket.com/albums/f286/CAVX/The%20235%20SET%20UP/T221x9PassMode.jpg
Then with the lens in place, the image should look like this.
http://i49.photobucket.com/albums/f286/CAVX/The%20235%20SET%20UP/T221x9StretchMode.jpg
And you should have a 2.35:1 image...

Mark

skhattane,

Very cool DIY lens! Very neat work.
Here are my original prisms...
http://i49.photobucket.com/albums/f286/CAVX/New%20Lens%20Production/DSCF2421.jpg
http://i49.photobucket.com/albums/f286/CAVX/New%20Lens%20Production/Older%20Lens/The2prismlens3.jpg

Mark

Hi mark,

Your prisms are very great look. :cool:
The specifications of our prisms :

http://skhattane2000.free.fr/Plans1.jpg

Here my sample :
http://skhattane2000.free.fr/pdiy001.jpg
http://skhattane2000.free.fr/pdiy002.jpg
http://skhattane2000.free.fr/pdiy005.jpg
http://skhattane2000.free.fr/pdiy006.jpg

Here the result in projection :

http://skhattane2000.free.fr/Mire2.35test.jpg
http://skhattane2000.free.fr/p001.jpg
http://skhattane2000.free.fr/p007.jpg
http://skhattane2000.free.fr/p008.jpg
http://skhattane2000.free.fr/p009.jpg

The prisms are in glass of 2mm (no antireflection, it's just a sample).
The liquid is "glycérine" (I don't know the word in english). Refraction index : 1.473

The futur sample will be in BK7 (optical material) with antireflection coating, etc...
All specifications and lot of screen of many realisation are on hcfr (the french forum). Lot of informations. No pbl to post in english on the french forum ;)

sam

Very cool! We call it "Glycerine" as well, but these are the first screen shots I've seen using it...
I've since built a 4 prism lens. Have you tried that yet?

Mark

I've since built a 4 prism lens. Have you tried that yet?
Mark

No, have you better results ?
Less chromatic diffractions or better geometry ?

those pictures of inaction scemes look great!

No, have you better results ?
Less chromatic diffractions or better geometry ?
I noticed less Chromatic Aberration and by reversing the prisms so that the hypotenuses of the right angled triangle (when viewed in plan) is out, better geometry...

Mark

QUESTION FOR THE BOARD- I'm having a little difficulty understinding something. An anamorphic lens allows you to use the full resolution of the display (mine is a 720P panasonic AE900 LCD) for 2.35:1 movies (okay, got it more projector pixels being used and no black bars on top and bottom). But the DVD player still is only outputting the usable 2.35:1 image using only 70% of the 480 horizontal lines possible. The black bars generated by the DVD player use up some of the resolution and can be removed by the display using aspect ratio to scale to use all 720 lines of the projector, but there is no way to get all 480 lines off the DVD in a 2/35:1 movie. Correct? Or am I missing something. I've toggled through all the output modes of my DVD player and they all put black bars on 2/35 images. help me understand where tthe increased resolution comes from - seems more like apparent resolution than true resolution benefit. -RANDOMCREEK

JIZZY1- What i'm saying is that I don't think you can remove those black bars via the DVD player. With the AE900 all you need to do is use aspect ratio button on the remote (second button up from the bottom left). This will allow the anomorphic lens to stretch the picture to 2.35:1. My issue is, however, that if you do this all you acheive is using more of the LCD panel (i.e all 720 pixels). Your not getting full 480 lines of DVD output- still only 400 (or something like that). I thought the point was to get the DVD player to output 480 horizontal lines of i2.35:1 mage (albeit squished to 16x9 aspect), then the projector to use all it's pixels in 16x9 mode (image still squished) and then anamorphic lens corrects the aspect and you'd end up with a higher resolution image on the screen. But I now am not so sure it works like that. The benefit is more display lines- not more image lines. Like having a TV with smaller pitch- this may provide more apparent resolution and reduce screen door effect, but no change in true resolution. The Panny already has smooth screen and i can sit 2 feet away from it and watch it without any screen door. IF there is a way to get greater true resolution I'm in, but can someone explain to us new to this how it's done- I'm not sure i understand.

It just became clear to me now that HD-DVD/BlueRay are noit being designd with the hometheater enthusiast in mind- at least not us front projection guys. All that disc space and the 2.35:1 cinemascope movies are still going to have black bars on top and bottom that you cna't get rid of and even using an anamorphic lens these epic movies will still have less true resolution than 16x9 throw away specials and made for TV movies and sitcoms. Great. I can understand why the DVD format did not consider this an issue worthy of consideration as most of us (none of us probably) were big screen junkies at the time DVD evolved, but why HD-DVD and BlueRAy specs do not have ability to output full resolution (720/1080i) for 2.35:1 cinemascope (in a squished format so anamorphic lens could be used in front projection with anamorphic lens) to get maximum resolution (and constand height functionality, full use of display resolution, etc) is just plain wrong. The most resolution is needed for front projection home theater and cinemascope aspect. It will be the same problem all over again-granted the overalll detail will be better than DVD but again the epic movies we like to watch the most and project bigger will be less detailed than 16x9 formatted junk. I'm probalby preaching to the choir here, but I has this issue ever been brought up as an issue to the HD consortiums? It's just like the highways they build here in Pennsylvania - every one has a bottleneck desigend in- engineered obsolescence. great.

2.35:1 CIH is about one thing - recreating the way it was meant to be seen. You can crunch rez numbers all day if you like. In the end, we have true widescreen images regardless of how much rez we have available to us to make them, our ARs are correct an the bigger AR is bigger...

We can only hope that these new generation formats do indeed offer that extra bit for cinema scope presentation...

Mark

It just became clear to me now that HD-DVD/BlueRay are noit being designd with the hometheater enthusiast in mind- at least not us front projection guys. All that disc space and the 2.35:1 cinemascope movies are still going to have black bars on top and bottom that you cna't get rid of and even using an anamorphic lens these epic movies will still have less true resolution than 16x9 throw away specials and made for TV movies and sitcoms. Great. I can understand why the DVD format did not consider this an issue worthy of consideration as most of us (none of us probably) were big screen junkies at the time DVD evolved, but why HD-DVD and BlueRAy specs do not have ability to output full resolution (720/1080i) for 2.35:1 cinemascope (in a squished format so anamorphic lens could be used in front projection with anamorphic lens) to get maximum resolution (and constand height functionality, full use of display resolution, etc) is just plain wrong. The most resolution is needed for front projection home theater and cinemascope aspect. It will be the same problem all over again-granted the overalll detail will be better than DVD but again the epic movies we like to watch the most and project bigger will be less detailed than 16x9 formatted junk. I'm probalby preaching to the choir here, but I has this issue ever been brought up as an issue to the HD consortiums? It's just like the highways they build here in Pennsylvania - every one has a bottleneck desigend in- engineered obsolescence. great.

No anamorphic Blu Ray / HD DVD 2.35:1 movies? What a disappointment.. :mad:

If this is true I see no point in optomizing my HT for cinemascope movies . Since the best res will be 16:9 why not go with a 16:9 screen.

You guys were right, but it's annoying. I have to set my dvd player to 480p before i get the vertical stretch option on the projector. but it works great!

No anamorphic Blu Ray / HD DVD 2.35:1 movies? What a disappointment..

If this is true I see no point in optomizing my HT for cinemascope movies . Since the best res will be 16:9 why not go with a 16:9 screen.

Because it's not just about resolution. It's about the extra width you get with a 2.35 screen. As it's been said, it's the difference between it looking like a giant tv and like a cinema.

Plus, you can get full resolution for 16x9 movies by removing the lens or using passthrough mode on the prismasonics.

Trust me, once you've seen a Constant Height setup for movies you wont go back.

Trust me, once you've seen a Constant Height setup for movies you wont go back.

Too true :D

Mark

My 1st CH theater experience will most likely be Mr. Poindexter's when he gets it finished in a couple months. Of course after that I'll be ruined for anything less and will probably be shopping for a new house to put it in my new CH HT. Oh well.... :D

Because it's not just about resolution. It's about the extra width you get with a 2.35 screen. As it's been said, it's the difference between it looking like a giant tv and like a cinema.

Yeah, I don't think many have one specific reason they're into CH, and certainly not "extra resolution". I haven't had my lens in place in quite a while, since my AE900 doesn't do the right scaling, so "added resolution" or "full use of the projector's panel" currently have nothing to do with why I bother. The aesthetic impact of it makes all the difference.

Jack,

the lack of scaling - is that over digital as the 700s certainly did a 4 x 3 zoom to give the so called "vertical stretch" over component...

Mark

Jack,

the lack of scaling - is that over digital as the 700s certainly did a 4 x 3 zoom to give the so called "vertical stretch" over component...

Mark

But won't that 4X3 zoom just get you back to 16X9, not 2:35.
Right?

Jack,

the lack of scaling - is that over digital as the 700s certainly did a 4 x 3 zoom to give the so called "vertical stretch" over component...

Mark

But won't that 4X3 zoom just get you back to 16X9 with the lens, not 2:35.
Right?

But won't that 4X3 zoom just get you back to 16X9, not 2:35.
Right?

No. It should give full panel image with no black bars and it should be tall and thin similar to the first T2 image I posted earlier. Then with the lens in place, the geometry will be restored to look like the 2nd image - AKA 2.35:1 or cinema scope...

Mark

I'm having the darndest time getting my retail 2.35 dvds to work on my 2.35 screen. I have the following:

Panny AE900U
2.35 Screen
UH-50 lens
Iodata Avel Link player 2.

Basically the problem is that i can not get my dvd player to stretch the 2.35 material vertically, thereby entirely removing the black bars before it gets to my projector. Is this how everyone else is doing it?

It seems like this needs to happen for it'll work? Please definately correct me if i'm wrong.


Obviously I am very new to this wonderful aspect, I also have a Panny AE900. After seeing an earlier post in regards to the AE-700. Can it be possible with AE-900 to project the 2.35 ratio without the prism conversion?

Thanks in advance just discovered this thread, I hope time is available to attempt the 2.65 ratio.

Obviously I am very new to this wonderful aspect, I also have a Panny AE900. After seeing an earlier post in regards to the AE-700. Can it be possible with AE-900 to project the 2.35 ratio without the prism conversion?

Thanks in advance just discovered this thread, I hope time is available to attempt the 2.65 ratio.

You still need the lens to correct the proportion of the image. The AE900 should be able to stretch the black bars out of the 2.35 image but the lens will then correct the stretched image.

Hi Brad,

IMO, what Tukkis suggests is the best way to achieve a constant height wide screen image.

However, there is another option, since you're using the Panasonic AE 900. You are fortunate in that the AE900 has quite a large zoom range compared to most projectors. I think it may be possible for you to maintain a constant height image by using the projector's zoom. What I mean is that you could zoom the picture larger so that the desired height stays constant for the wider aspect ratios. I'm not certain if the zoom range is sufficient for constant height at a ratio of 2.65:1, but I would think 2.35:1 is attainable.

Although this second option is not the preferred method for constant height, it might "get you into the game" until you're ready to spring for an anamorphic lens adapter. I used the zooming approach for a while before switching to the adapter and electronic image scaling several years ago. Once you see how that combination works, though, I bet you'll want to go that way :) .

The zoom method has been discussed time and time again. If you do this, you not only throw away valuable pixels, but you lose brightness as well. It is a quick fix solution to get you used to what you will be seeing, but it is not how to do a 2.35:1 CIH Set Up...

Mark

O.K.
For all of you Panasonic 900 owners, I have found a combination of equipment so I now have constant 2:35 image. (All with correct geometry)
#1 is my Samsung 360 HD directv receiver.
#2 is my Panasonic RP-56 DVD player
#3 the Panasonic 900.
Heres how to configure it to have 2:35 AR at all times with all sources, including 16X9 HD.
Yes, I know I'm not gaining the extra light output with the full panel but The picture is plenty bright.
The dvd players component (out) goes to the Samsung HD receivers component (in).
The HD receivers DVI (out) goes to the Panasonics 900 HDMI in (conversion plug) DVI to HDMI.
The HD receiver must be set for 4X3 TV Letterbox in the menu.
Set your PJ to 16X9.
Set your DVD player to 16X9.
Thats all there is to it.
I know I said all sources will be 2:35. I forgot , not regular SD channels, these will still show in 16X9.
Since I rarely use my projector for regular TV this set up fits my situation perfectly.
I'm sure there is other equipment combos with the 900 that will achieve the same results.
The only time you will need to change any of your settings with your remote is if your watching a "real" 2:35 movie, you will need to change the receivers output with your remote to 4X3 FULL.
Again, with all of these settings I am getting the full picture and the proper geometry.
Also, my receiver upconverts to 1080i, 720p, or 480p, and this works with all inputs.

The HD receiver must be set for 4X3 TV Letterbox in the menu.
Set your PJ to 16X9.
Set your DVD player to 16X9.
Thats all there is to it.


Are you talking about the zoom method here? There is no mention of what lens you might be using, and I am curious as to why you've set the HD box to 4 x 3 and then the projector to 16:9.

A 4 x 3 source on a 16:9 display would give you a stretched image even without a lens...

Maybe a little more info...

Mark

No lens in use.
All of the settings and equipment listed are all that is needed to display a 2:35 AR full time. The only exception is SD tv, in that case the image goes to 16X9 ( too tall for the screen) and zooming the image down would be required to fit the screen vertically. Since I rarely use my PJ for SDtv, I have a constant 2:35 AR (with all sources) without a scaler or lens.

Whilst I am sure your happy with the results, what you have created is a full screen set up with a few limitations including the fact that you would be cropping your 16:9 images to fill the screen and well as the fact that you are not able to use your full vertical rez of the display...

A true 2.35:1 CIH set up means that your image height always remains the same, but your width will vary depending on the OAR of the source...

Mark

I understand I'm not getting the extra light output I would with a lens, but as I said before I prefer having 2:35 AR for ALL of my veiwing on my pj. Sports, Movies ect.
One of the nice this about it is, no messing with any adjustments or lens adjustments, scaler adjustment or masking. Maybe we should start a "Contsant "2:35 AR thread.
Actually I think my setup is more "true" 2:35 setup since I'm not limited to use it for just 2:35 movies.

understand I'm not getting the extra light output I would with a lens, but as I said before I prefer having 2:35 AR for ALL of my veiwing on my pj. Sports, Movies ect.
One of the nice this about it is, no messing with any adjustments or lens adjustments, scaler adjustment or masking. Maybe we should start a "Contsant "2:35 AR thread.
Actually I think my setup is more "true" 2:35 setup since I'm not limited to use it for just 2:35 movies.


Each to their own. I would love to use 2.35 for everything, unfortunately all the material out there is shot in different formats.

Over at the what looks to be the French equivalent of AVS there is huge thread (1800+ posts) in the DIY section on making an anamorphic lens.

I had mixed success using google to translate as it only seemed to do some of the messages ?? but the short verison seems to be that they have designed an anamorphic lens and will be doing a production run for forum readers.

As far as price / ETA, etc I'm not too sure, so if anyone here can read french could you check it out and perhaps summarise it for the rest of us ??

www.homecinema-fr.com

Is that by THIS GUY (http://www.avsforum.com/avs-vb/showthread.php?p=7191680&&#post7191680) ?

Mark

Is that by THIS GUY (http://www.avsforum.com/avs-vb/showthread.php?p=7191680&&#post7191680) ?

Mark


Yes, he is involved, but it seems that they are setting up to manufacture a batch for forum readers. 150 euros for a manual, 300 for a motorized was mentioned.

Babelfish seems to do a better job on the translation, but the thread is 120 pages long ....

Still reading

While the use of an anamorphic lens to do a horizontal streach and a scaler to do a vertical streach of the image so as to use the full vertical resolution of the display device may have benefits when using a projector with a 720p native resolution and when the video source is 1080i or 1080p. However, I'm not convinced this is the best solution for displaying 2.35:1 material if you have a projector with a native 1080 x 1920 pixel resolution (such as the Sony Ruby or one of the soon to be available 1080p DLP front projectors). Since these projectors exactly match the resolution of the 1080i and 1080p source material (Blu-ray supports 1080p) any additional scaling to do a vertical streach would introduce some level of digital artifacts. With such 1080p projectors you may very well get better results by using the projector's zoom to enlarge a 2.35:1 image to fill the screen. You would be getting all of the resolution available from the 1080i or 1080p source material and would avoid any scaling artifacts.

Ron Jones

With such 1080p projectors you may very well get better results by using the projector's zoom to enlarge a 2.35:1 image to fill the screen. You would be getting all of the resolution available from the 1080i or 1080p source material and would avoid any scaling artifacts.

By using the zoom, you are magnifying the size of the pixels and the gaps between pixels, which will accentuate Screen Door Effect, and will dispurse your light over a wider area, making the image dimmer. A good video processor will have negligible scaling artifacts, and is preferable to using the zoom.

With such 1080p projectors you may very well get better results by using the projector's zoom to enlarge a 2.35:1 image to fill the screen. You would be getting all of the resolution available from the 1080i or 1080p source material and would avoid any scaling artifacts.

Ron Jones

Also worth considering is that many of us have large collections of DVD's numbering in the 100's or 1000's even, many of these titles probably won't be available on BRD or HD-DVD for years (if ever).

Personally I won't be inclined to upgrade my current collection, with a few expections (LOTR, Star Wars obviously). Will HD or BRD look better - you bet, but will I stop watching DVD's, no way.

A good HTPC or external scaler gives more flexibility and shouldn't introduce many (if any) noticeable artifacts.

So for me anyway, with a soon to be mixed collection, a scaler/htpc is the only way to go, as I want the brightest best image I can get across all media, without having to constantly adjust my projector zoom.

With such 1080p projectors you may very well get better results by using the projector's zoom to enlarge a 2.35:1 image to fill the screen. You would be getting all of the resolution available from the 1080i or 1080p source material and would avoid any scaling artifacts.

Ron Jones

It has been mentioned in other threads that BRD and HD-DVD don't support anamorphic 2.35:1 so you are still using one third of those 1080 lines to project black bars.

To me this just begs to be scaled :)

It has been mentioned in other threads that BRD and HD-DVD don't support anamorphic 2.35:1 so you are still using one third of those 1080 lines to project black bars.

Does anyone have a link that confirms that HD DVD or BRD are still only 16:9?

Mark

I notice there are anamorphic lenses available on ebay occassionally. I have a panasonic ae900u and I am wondering if anyone has an opinion as to which anamorphic lenses would be usable with the panny?

Careful with the Ebay lenses, as most are film lenses not video lenes. Film or cinema scope lenses have 2x stretch where video anamorphic lenes have just 1.33 stretch. Trying to use a 2x with your HT (It can be done with a good scaler) could prove frustrating...

Mark

I would certainly agree that you will get a brighter image using the anamorphic lens (rather than just the zoom to fill the screen). My point was if using a native 1080p resolution projector (and hopefully one with minimal SDE) the zoom approach for 1080i/1080p HD source material might look a little better by avoiding the need for any scaling and any potential loss of horizontal resolution or other distortions due to the use of the additional anamorphic lens.

Ron Jones

Another problem with zoom - don't most PJ's shift image when zooming?

TC

Correct...

Mark

Another problem with zoom - don't most PJ's shift image when zooming?
Yeah, I have the zoom/shift drill down to under a minute on my 900.

And with a lens, it could be as simple as pushing a buttom. I don't even have to get out of my chair...

Mark :D

I don't even have to get out of my chair...

Anything that allows me to make that statement is, in my estimation, a very good thing. Not that I'm lazy, mind you.

And with a lens, it could be as simple as pushing a buttom. I don't even have to get out of my chair...
I do miss that. :)

A few pages ago, someone posted an Excel file that would do all the calculations for 2.35:1. I'm on a Mac, and I have no way to open it, so would anyone be willing to input my specifications into the calculator?

I have an 18' throw, using the HD72 and one of the Prismasonic H lenses. I'm looking at a 118x50" screen. I'm not sure what other numbers would be needed.

It would be much appreciated if someone would do this for me!

Try THIS (http://www.myhometheater.homestead.com/viewingdistancecalculator.html) calculator for viewing angles and seating distances. Just ignore the height...

Mark

Try THIS (http://www.myhometheater.homestead.com/viewingdistancecalculator.html) calculator for viewing angles and seating distances. Just ignore the height...

MarkThanks, I've seen that one, but maybe you could clear up some confusion for me? Do I input the width of my 2.25:1 screen (118") or the width of the equivalent screen in 16:9 (which I think would be 92.5", which is screen height x 1.85)? This is my first dedicated home theater, and I'm still confused a bit.

The viewing angle actually does [EDIT: NOT] change for any AR. So just input your width of the 2.35:1 (2.25?) screen and then the distance you want to sit at, and it will tell you both the THX min and preferred as well as SMPTE recommendations. The thing about that calculator, it was originally designed for cinema scope 2.35:1, but adopted for 1.78:1 for HT...

[why do I keep forgetting the not...]

Mark

Thanks, CAVX!

Hi all GREAT thread and I am sold on the 2.35:1 screen size, but I have a question or 2. I will be getting a Sanyo Z4 PJ, Denon 1920 DVD Player still deciding on the Lens, but the Prismasonic H-600M looks like a Good Choice.
The Theater is still under construction so I have some time to research this farther and get some Pricing.

My Question is If I went with this setup would I still need a Scaler?? if yes any reccomendations??

The Room is 11'x19' and the closest to the screen is 12' what would be a good size screen for this room??

Also if there is another combo that would work PJ or DVD Player that would help cut the cost of getting a scaler I am all ears, but I am really sold on the Sanyo Z4 PJ, so if you reccomend any thing Ill look into it but If you did reccomend a new DVD Player it would have to be capable of Both DVD-A / SACD Audio and Upoconvert via HDMI. THNX :)

-Gerald

To answer the first question - no you don't need a scaler, but one would make life better in the future so that all video sources can be used, not just your DVD player...

The second question - it depends on the brightness of the projector/light control etc, but anywhere from 94 inches wide will work in your room. A 94 inch screen viewed from a distance of 12 feet will give you a viewing angle of 36 degrees which is preferred for 2.35:1, but you might want to go larger if you intend to instal multiple rows...

Mark

Hmm it did say in the Guide on things needed was a scaler to perform the vertical stretch will my DVD player or PJ do this ??

If I did get a scaler in the future, cause I plan on watchin HDTV in my theater as well, what will the scaler do for the HD viewing??

I will probally go with the 94" wide screen as that would take up almost the entire wall with a lil room to spare on the side for the curtains for masking.

THNX CAVX!! :)

Depending on how the signal is passed. It seems that most projectors will not allow the HD signal to be displayed on 4 x 3 zoom over digital, but it does work on component...

Mark

Oh then the Scaler would allow me to see the picture in a 2.35:1 ratio?? But I am not going to do that cause the Upconvert only works thru DVI :(

I will not mind watching the 16:9 format I could always setup the curtains to mask it but will I have Black bars on the top and bottom of the screen??

why does this have to be so complicated hehe?? :D

Most likely you won't convert HDTV into 2.35:1 as you would end up losing the top and bottom of the image. HDTV is generally 16:9, but from time to time, a movie is presented in 2.35:1, and then your 235CIH comes into its own...

Mark

I'm jumping into this adventure.....

I just read all of this and figured some of it out, but would like to ask a few questions about the scaler too. I'm thinking about a 110-120" screen, the Sammy 710 projector and I have no clue on a lens yet. I planned on getting a scaler as well, but perhaps I'll get a lens forst and then "upgrade" with a scaler.

Assuming I have a lens, but no scaler, I'll have no problem viewing 2.35 content with the lens in place and no black bars, and HDTV and 1.85 without the lens, but with bars on the sides that I can easily mask right?

Assuming I'm right so far, is the scaler is not 100% required right? I would still like to have one because I've seen what it can do to better the picture quality, but at least to get started, do you really need it?

Finally, I see that Panamorph has a $495 lens.... the U80. Thoughts on this one? I'm going to do a search, but I figured I'd throw this at the end of this post. Thanks!

Assuming I have a lens, but no scaler, I'll have no problem viewing 2.35 content with the lens in place and no black bars, and HDTV and 1.85 without the lens, but with bars on the sides that I can easily mask right?
Correct. I use a hinged system and it works a treat (thanks Cinemax :))...

Assuming I'm right so far, is the scaler is not 100% required right? I would still like to have one because I've seen what it can do to better the picture quality, but at least to get started, do you really need it?

I would say it is the cream on the cake. It is not needed but certainly completes it...

I'll let some one else comment on the U80 'cause I need to do more research on that one...

Mark

Thanks for the response! I've found a bit to read on the U80. Also came across the P752 and U15 on some used marketplace sites. There's just so much to read on each these..... finding the time to do it is tough!

So is it a VC or HE lens?

Mark

Mark,

The U80 is VC.

Scott

So the UH-50 is their only HE lens?

Mark

yes and no. According to Shawn, they are no longer mass marketing this lens due to some PQ issues. However, he indicated about a week ago that some are available.

is there a way to setup the system so that the masking and lens are adjusted automatically according to the AR of the signal being watched. For example, it is easy enough for me to adjust the lens or move it when necessary but I am currently setting up a system for my father-in-law who doesn't want to mess with anything between movies (any ratio) and HD TV. I want the 2.35 but want to find out how simple it can be for him to operate. Ideally, the lens would be engaged if necessary when a wide movie is watched and disengaged otherwise. Thanks

I've long been convinced that I wanted a CIH setup. "http://www.panamorph.com/Products.html Vertical or Horizontal" convinced me that I want the kind of anamorphic lens that compresses vertically.What do I do with the anamorphic lens when I want to watch non 2.35 (scope)films?

1. Leave the lens in place all the time for all aspect ratios. This implies a loss in resolution and brightness for anything other than 2.35 films as the sides of the picture are now wasted on black pillar bars.OK, this seems like the way to go (for me/for the best possible WAF,) but I'm really having trouble wrapping my brain around this one...

I get it (I think) that TheaterTek gives me excellent control over the aspect ratio - including applying any horizontal squeeze I might need (so that the anamorphic lens can then squeeze it back vertically.) Is that correct?

But what if I'm watching something other than a movie? (Ergo I'm not using TT.) Let's say I'm watching an HDTV program that I recorded using a MyHD card. Or I'm bringing in a signal from my DirecTiVo using a capture card and Dscaler. How do I get the image squeezed horizontally in those scenarios (without TT to do it for me?)

Also, there's a lot of mention about the 4805's ability to stretch the image such that an HTPC is not necessary. The HD72 I'm getting has 4 aspect ratio buttons on the remote - 4:3, 16:9, Letter Box, and Native. Does that mean it will do this, too?

If you want to keep the lens in place all the time, you need 2.35 material vertical stretched and the lens will do the rest. For 16x9 material what you want is 4x3 mode so that the scaler/software puts black pillar bars left/right of the 16x9 image.

Think of it kinda like 2.35 is like 16x9 where you use the whole panel and 16x9 is like watching 4x3 on a 16x9 projector where there is black bars left and right.

Even though you're using less resolution it's not as noticeable as you think because you're still using the full resolution in height.

OK. That makes sense. But I'm not sure there's any way of telling MyHD to output in 4:3 mode. Unless the HD72 will do it...?

If it's going to be anywhere it'll be in the software side of things.

Not sure if that projector can adjust the ratio from HDMI/DVI but if it does you want 4x3 mode on the projector.

I have not read through all the threads on the 2.35 constant height topic so forgive me if what I am about to say has already been posted.

With a 1920x1080 projector, if a picture was zoomed so that a 2.35 picture filled a 2.35 screen with the black bars extending off the screen, the loss of vertical pixels for the picture itself would be approx. 25%. That means there would be about 818 pixels making up the picture vertically which is approx. 100 pixels more than a 720p projector puts out in 16:9 mode. So, if the projector is zoomed out so that the picture fills the screen and the black bars extend beyond the top and bottom of the screen, voila, a 2.35 image without the anamorphic lens. Black felt or velour above and below the screen should take care of any stray light and you have a picture made up of almost 1.6 million pixels which is still about 60% greater than a 16:9 image from a 1280 x 720 projector. This eliminates the cost of the anamorhic lense and scaler with aspect control, distortion and chromatic aberation and changing the lense setting when going from 2.35 to 1.78 ratio. A 54" high 2.35 image would have approx. 8.5" bars, top and bottom.

Assuming the projctor has enough lumens for an adequately bright picture, the only potential down side to this approach that I can see is that the image position may shift as the lens is zoomed.

Any thoughts on the subject?

That means there would be about 818 pixels making up the picture vertically which is approx. 100 pixels more than a 720p projector puts out in 16:9 mode.If you feed a 1080 signal to a native 720p projector, it's going to scale it down to 1280 x 720.

I'm not talking about feeding a 1080 signal to a 720 projector. I am talking about a 1080 projector with 1080 source material.

OK. That makes sense. But I'm not sure there's any way of telling MyHD to output in 4:3 mode. Unless the HD72 will do it...?

The HD72 will do all the scaling for you for any input resolution (480i, 480p, 720p, 1080i, 1080p, etc...)

LBX for 2.35:1, 4:3 for eveything else but you're throwing away 25% of the source to create gray/black bars on the side (1280x720 -> 960x720 + 160 lines of black on each side) when using 4:3 mode.

The whole point of using an anamorphic lens is to use every pixel on the 16:9 panel rather than "wasting" the potential luminosity from all those (black bar) pixels.

Any thoughts on the subject?

This is what some users of the ae900 are doing and 2.35 SD DVDs. You need a huge zoom range (ae900 has up to 2x zoom), lens shift, and black paint or felt surrounding the screen to absorb all the light spill from the psuedo black/gray bars. You have to zoom, shift, and refocus each time you do this, but it works!

The whole point of using an anamorphic lens is to use every pixel on the 16:9 panel rather than "wasting" the potential luminosity from all those (black bar) pixels.

It is for most. That is why I got Prismasonic lens with pass mode - so I still have full panel utilization for 16:9 or less material. I only stretch the picture for 2.35 movies and lose nothing for HDTV, etc. The best of both worlds. That's the drawback of VC (like panamorph) lenses which typically have to leave the lens in place.

If you leave the lens in place and want correct geometry for anything less than 2.35:1 you'll have to create the black bars on the panel.

you're throwing away 25% of the source to create gray/black bars on the side (1280x720 -> 960x720 + 160 lines of black on each side) when using 4:3 mode.I'm OK with that. The whole appeal of CIH is that the picture is at its most impressive with 2.35:1 source material. As the a.r. goes down from there, so does the overall size of the image and the relative impact - exactly as it should be, IMO.

The thing I was unclear about was whether the HD72 would properly squeeze and pillar box 16:9, 1.85:1 and 4:3 source material so that I could get away with leaving the anamorphic lens in place at all times. I now have the HD72, so I guess I can play with this to my heart's content, but I don't yet have an anamorphic lens.

That will still depend on the source. A scaler or HTPC will the best job, but DVD players such as the Samsung HD-950 also provide both horizontal squeeze (useful for 4 x 3 material) and a vertical stretch which is used for 2.35:1.

In the case of this player, the projector setting can be 16:9.

I don't have a scaler, and do own the HD-950, but prefer to use a different player for video.

In this case I use the projector modes (4 x 3 + lens = 16:9 and 4 x 3 zoom + lens = 21:9)...

Mark

I'm OK with that. The whole appeal of CIH is that the picture is at its most impressive with 2.35:1 source material. As the a.r. goes down from there, so does the overall size of the image and the relative impact - exactly as it should be, IMO.
That, to me, is what CIH is about, and why it's called what it's called. Not brightness, pixels, etc., but the theaterical/presentation aspect.

This is what some users of the ae900 are doing and 2.35 SD DVDs. You need a huge zoom range (ae900 has up to 2x zoom), lens shift, and black paint or felt surrounding the screen to absorb all the light spill from the psuedo black/gray bars. You have to zoom, shift, and refocus each time you do this, but it works!
All true, and a PITA...but it does work. :) DVD PQ compared to using my Panamorph 752 is comparable, but I suspect proper scaling of HD media would shift things in favor of full panel utilization.

I suspect proper scaling of HD media would shift things in favor of full panel utilization.

I can't wait to read about the results from early adopters...

Mark

Great GReat Info:

Would it be possible to list the Pro's and Con's of each of the 3 Methods:

1)Constant Height
2)Constant Width
3)Constant Area

Thanks

Lon

Great GReat Info:

Would it be possible to list the Pro's and Con's of each of the 3 Methods:

1)Constant Height
2)Constant Width
3)Constant Area

Thanks

Lon

I think this has been done before but here goes...

1)Constant Height - 2.35:1

Pros - all ARs at the same height using full vertical rez of the projector. Can be done with either a HE or VC anamorphic lens.
Cons - some lens distortion (pincushion or barrel) and some CA depending on the type of lens used...

2)Constant Width - 1.78:1

Pros - works with or without a lens but better with.
Cons - Letter boxes the larger AR meaning vertical pixels are wasted on black bars is not using a VC lens.

3)Constant Area - 2.0:1

Pros- allows image area to roughly be the same between 2.35 and 1.78.
Cons - requires zooming to achieve maximum screen usage.

Having tried all three methods, I prefer constant image height...

Mark

I'm going to take another stab at that from more of a "what does that mean to me" standpoint...

Constant Height
Pros: Cinemascope/Anamorphic Widescreen (2.35/2.39/2.40:1) images take up the entire screen, so big, sweeping, epic films from Ben Hur to Braveheart to Lord of the Rings have the greatest impact, while lower aspect ratios are less impressive because they are pillar-boxed (black bars on the sides) so they aren't as large/don't fill the screen. Many make the case that this is the way it should be... a 2.35:1 film should have greater impact and be more impressive than a 1.78:1 or 1.85:1 film which in turn should have greater impact than reruns of Gilligan's Island in 4:3/1.33:1. Side note #1: Cinemascope films are shot using an anamorphic lens on the camera to capture a widescreen image on film that has a much smaller aspect ratio. ("Academy format 35mm film is 1.37:1). By using a 2.35:1 screen with a 16:9 projector+anamorphic lens, you're basically just reversing the process in which these films were created. Side note #2: Historically, Hollywood blockbusters were all shot in Cinemascope, and commercial theaters all had 2.40:1 screens. When displaying a film shot in something other than Cinemascope, they would draw curtains to mask the unused portions of the screen on both sides.
Cons: The new crop of cutting edge filmmakers are shooting their films digitally, in native HDTV, so the film is presented in a lower aspect ratio. A good example of this is Sin City. Robert Rodriguez used state-of-the-art equipment and techniques, shooting the film in 1080p. Should Sin City have less impact than LOTR? Certainly not if you're a huge fan of the film, but disregarding that specific film and any biases you have for/against it, the fact is that Cinemascope is film-based, and technology is moving away from that and toward digital. Do we "penalize" modern films, even those that are "state-of-the-art" simply because they don't conform to a decades-old standard?

Constant Width
Pros: Assuming a 16:9 "widescreen" screen, the biggest pro here is that the screen is the same aspect ratio as an ATSC/HDTV picture. Virtually all of the top TV shows that you watch via digital cable, satellite or OTA will fill your screen because they have the same exact A.R. Likewise, modern (digital) films (as mentioned above) will fill the screen. (Technically, Sin City at 1.85:1 would have very small black bars top and bottom; none of the options for dealing with this are overly objectionable - leave them displayed, vertically stretch the image, or zoom and project a very small amount of the image off the sides of the screen.)
Cons: Classic, film-based Cinemascope epics are presented with thick black bars top and bottom. They don't fill the screen and have less impact than 1.78/1.85:1 material. Should King Kong be "penalized" because Peter Jackson chose film over digital? Side note #3: Just because "modern/state-of-the-art" films are shot digitally doesn't mean they can't be shown in 2.35:1. George Lucas shot the last two Star Wars episodes in digital 1080p. I don't know if he applied some sort of digital anamorphic compression or what, but almost anything is possible digitally. Ergo, it's quite possible that future SOTA films could be presented in 2.35:1.

Constant Area
I really can't speak to this as I've never understood it. IMO, it's so compromised that there are no pros, but I'm sure CA advocates have their reasons.

I'm going to take another stab at that from more of a "what does that mean to me" standpoint...

Constant Height
Pros: Cinemascope/Anamorphic Widescreen (2.35/2.39/2.40:1) images take up the entire screen, so big, sweeping, epic films from Ben Hur to Braveheart to Lord of the Rings have the greatest impact, while lower aspect ratios are less impressive because they are pillar-boxed (black bars on the sides) so they aren't as large/don't fill the screen. Many make the case that this is the way it should be... a 2.35:1 film should have greater impact and be more impressive than a 1.78:1 or 1.85:1 film which in turn should have greater impact than reruns of Gilligan's Island in 4:3/1.33:1. Side note #1: Cinemascope films are shot using an anamorphic lens on the camera to capture a widescreen image on film that has a much smaller aspect ratio. ("Academy format 35mm film is 1.37:1). By using a 2.35:1 screen with a 16:9 projector+anamorphic lens, you're basically just reversing the process in which these films were created. Side note #2: Historically, Hollywood blockbusters were all shot in Cinemascope, and commercial theaters all had 2.40:1 screens. When displaying a film shot in something other than Cinemascope, they would draw curtains to mask the unused portions of the screen on both sides.
Cons: The new crop of cutting edge filmmakers are shooting their films digitally, in native HDTV, so the film is presented in a lower aspect ratio. A good example of this is Sin City. Robert Rodriguez used state-of-the-art equipment and techniques, shooting the film in 1080p. Should Sin City have less impact than LOTR? Certainly not if you're a huge fan of the film, but disregarding that specific film and any biases you have for/against it, the fact is that Cinemascope is film-based, and technology is moving away from that and toward digital. Do we "penalize" modern films, even those that are "state-of-the-art" simply because they don't conform to a decades-old standard?

Constant Width
Pros: Assuming a 16:9 "widescreen" screen, the biggest pro here is that the screen is the same aspect ratio as an ATSC/HDTV picture. Virtually all of the top TV shows that you watch via digital cable, satellite or OTA will fill your screen because they have the same exact A.R. Likewise, modern (digital) films (as mentioned above) will fill the screen. (Technically, Sin City at 1.85:1 would have very small black bars top and bottom; none of the options for dealing with this are overly objectionable - leave them displayed, vertically stretch the image, or zoom and project a very small amount of the image off the sides of the screen.)
Cons: Classic, film-based Cinemascope epics are presented with thick black bars top and bottom. They don't fill the screen and have less impact than 1.78/1.85:1 material. Should King Kong be "penalized" because Peter Jackson chose film over digital? Side note #3: Just because "modern/state-of-the-art" films are shot digitally doesn't mean they can't be shown in 2.35:1. George Lucas shot the last two Star Wars episodes in digital 1080p. I don't know if he applied some sort of digital anamorphic compression or what, but almost anything is possible digitally. Ergo, it's quite possible that future SOTA films could be presented in 2.35:1.

Constant Area
I really can't speak to this as I've never understood it. IMO, it's so compromised that there are no pros, but I'm sure CA advocates have their reasons.


With Constant Width couldn't one use a Vertical anamorphic lense and not have black bars on the top and bottom?

can I use my projector for a 2.35:1 a/r. (Optoma ep758) XGA 1024x768 (4:3).
I'm using it as a 16:9 now with a screen size of 118", height 54" width 104" and pj. distance from the screen is 18-19ft. I also have a (DVDO VP30 Scaler). If so what type of lens do I use (horizontal..?)
Steve Carr.

Cinemascope is film-based, and technology is moving away from that and toward digital.
Good point Donny, but the last 2 SW films were shot in digital, and they are 235...
With Constant Width couldn't one use a Vertical anamorphic lense and not have black bars on the top and bottom?
Yes. A VC can be used to give 100% panel use for a 235 film whilst being projected on to a 16:9 screen...
can I use my projector for a 2.35:1 a/r. (Optoma ep758) XGA 1024x768 (4:3).
I'm using it as a 16:9 now with a screen size of 118", height 54" width 104" and pj. distance from the screen is 18-19ft. I also have a (DVDO VP30 Scaler). If so what type of lens do I use (horizontal..?)
Steve Carr.
It has been done before by using a 2x stretch (film) lens providing that you can find one with a large enough rear optic...

Mark

Certainly not if you're a huge fan of the film, but disregarding that specific film and any biases you have for/against it, the fact is that Cinemascope is film-based, and technology is moving away from that and toward digital.

While I agree that most new TV shows are shooting for 16x9 (1.78) I think you'll notice more and more films shot are using 2.35.

Even comedies and romance these days which were traditionally 1.85 ratio films are being shot in 2.35

I think in part because lots of people have HDTV that are widescreen so they want to get more people back to the cinemas with a ratio that very few people can reproduce with the impact it's meant to have aka *2.35*

Exactly. On new prints of adds during the pre-show, most adds are flat 1.85:1 (or maybe they are actually 1.78:1 but due to just 4% difference, who can really tell?) and are just like watching a really BIG TV. But when those curtains open up, you know your in for a treat that most will never have in their homes...

Mark

Have any DVD players other than the Samsung HD-950 and Momitsu V880 been identified as providing the vertical stretch function for 2.35:1 content?

the last 2 SW films were shot in digital, and they are 235... I know. I said that. Just because "modern/state-of-the-art" films are shot digitally doesn't mean they can't be shown in 2.35:1. George Lucas shot the last two Star Wars episodes in digital 1080p. I don't know if he applied some sort of digital anamorphic compression or whatAny idea what method Lucas used to go from digital 1080p to the 2.35:1 A.R.?

While I agree that most new TV shows are shooting for 16x9 (1.78) I think you'll notice more and more films shot are using 2.35.

Even comedies and romance these days which were traditionally 1.85 ratio films are being shot in 2.35

I think in part because lots of people have HDTV that are widescreen so they want to get more people back to the cinemas with a ratio that very few people can reproduce with the impact it's meant to have aka *2.35*Interesting point. I hadn't noticed that, but I'm glad to hear it. I'm not sure it's a studio choice, though... generally it's the producer or director making that call.

As technology marches on and more power/capability becomes cheaper and cheaper, I think we'll start seeing indy filmmakers with scaled-down versions of Robert Rodriguez's ranch. (Sort of a "garage ILM" if you will.) As that happens, I suspect 2.35:1 will eventually become "old school". That's not to say that some of them won't opt to mask their digital creations down to 2.35, but I suspect that 2.35's days are (unfortunately) numbered. Just as multiplexes have supplanted the "El Capitan" and other iconic theaters of yesteryear, so, too, will 2.35:1 films slowly die off. :( The good news is, that's probably at least a couple of decades away.

Any idea what method Lucas used to go from digital 1080p to the 2.35:1 A.R.?
Based on footage I have seen, he kept the "action" between two horizontal lines that denoted the 2.35:1 frame on the 16:9 frame...

Mark

If you want to keep the lens in place all the time, you need 2.35 material vertical stretched and the lens will do the rest. For 16x9 material what you want is 4x3 mode so that the scaler/software puts black pillar bars left/right of the 16x9 image.

Think of it kinda like 2.35 is like 16x9 where you use the whole panel and 16x9 is like watching 4x3 on a 16x9 projector where there is black bars left and right.

Even though you're using less resolution it's not as noticeable as you think because you're still using the full resolution in height.

Is there an acceptable way of stretching a 16x9 image to 2.35:1 at this time? I was thinking about how my plasma or cable box stretches the image of SD material to fill my widescreen TV and was hoping that an HTPC or scaler could perform this function to eliminate the need for a 2-way masking system.

Thanks,
T.Wells

Yes it can be done, but no I would not say "acceptable".

I leave the lens in place, so to watch 16:9, I use the 4 x 3 mode and the lens does the stretch. To "fill" the screen, I can use 4 x 3 ZOOM. It remains geometry correct, but chops the top and bottom off the image - hence why I can watch 235 with no black bars...

If I select the 16:9 mode, I get full screen, but the image is now stretched, both by the projector and the lens...I do get to see the full image, but it stretched...

Mark

Yes it can be done, but no I would not say "acceptable".

I leave the lens in place, so to watch 16:9, I use the 4 x 3 mode and the lens does the stretch. To "fill" the screen, I can use 4 x 3 ZOOM. It remains geometry correct, but chops the top and bottom off the image - hence why I can watch 235 with no black bars...

If I select the 16:9 mode, I get full screen, but the image is now stretched, both by the projector and the lens...I do get to see the full image, but it stretched...

Mark

Thanks Mark. It looks like I'll be adding some sort of masking system to the budget if possible. I saw a recent post listing the known CIH masking systems. Since I already have a screen ready to mount, it looks like I'll be in the market for a frame with motorized masking.

Thanks again,
T.Wells

Okay, not sure exactly how to do the inbetween aspect ratios.

So, for 2.35:1 I simply stretch the image top to bottom. Easy enough.

For 16:9 I use pass mode with a lens, or remove it and re-adjust the projector to fill the screen top to bottom, ideally masking the left and right.

For 1.85:1...? If I'm understanding this correctly, in order to maintain proper proportions, the scaler needs to send the image to the projector with pillars on the side. Is this only accomplishable through advanced HTPC software or scalers - not through standard "16:9, zoom, letterbox" settings included in DVD software packages, and some projectors?

And on an un-related question, does anybody make a lens which would allow a projector such as the HC3000 (1280x768) to use the full pannel with proper geometry? Or am I getting a little too anal with wanting to get those extra 48 pixels on a CH setup?

Note: I don't have an HC3000, but it's on my short list of possible purchases.

Okay, not sure exactly how to do the inbetween aspect ratios.

So, for 2.35:1 I simply stretch the image top to bottom. Easy enough.
Correct. You will then either optically stretch (HE) or compress the image (VC)...
For 16:9 I use pass mode with a lens, or remove it and re-adjust the projector to fill the screen top to bottom, ideally masking the left and right.
With a HE, there should be no adjustment required (ISCO II is the exception) apart from maybe some slight re-focus...

For 1.85:1...? If I'm understanding this correctly, in order to maintain proper proportions, the scaler needs to send the image to the projector with pillars on the side. Is this only accomplishable through advanced HTPC software or scalers - not through standard "16:9, zoom, letterbox" settings included in DVD software packages, and some projectors?

Correct, you will need a scaler or HTPC for precise imaging. Most projectors will not allow you to see the 4% difference using 4 x 3 ZOOM of letterbox modes...

And on an un-related question, does anybody make a lens which would allow a projector such as the HC3000 (1280x768) to use the full pannel with proper geometry? Or am I getting a little too anal with wanting to get those extra 48 pixels on a CH setup?

Note: I don't have an HC3000, but it's on my short list of possible purchases.
The amount of horizontal squeeze applied electrically to a DVD (and DTV) is 33%. All anamorphic lenses for video are designed for a 33% stretch or compression to offset the standard amount. The projector you have listed is not a native 1.78:1, but rather 1.66:1. The only way to use the full panel is to employ a scaler, or your images will be a tad thin...

Mark

Thanks, that answers a bit. So if I understand correctly, for 1.85:1, the projector's 4:3 mode zoomed will get the image within 4% of correct geometry - not very noticeable unless perhaps a circle is displayed.

For all those oddball aspect ratios (1.66:1, 2.2:1, 2:1, etc) I guess it's best to just get a scaler and program it for all the different formats? Or are all DVD transfers from the oddball formats cropped to one of the more standard formats?

I'm going to start looking into DIY for now as getting a proper lens is too expensive for me right now. I'll be the one with the ghetto 2.35:1 CH setup. I'm even using a 4:3 projector at 800x600. I'd like to find out how to make a lens which will squish 4:3 to 2.35:1, but if I can't find that, or if even DIY is a bit pricy, I may just make a 16:9 which will work with this projector, and a future 16:9 projector.

Thanks, that answers a bit. So if I understand correctly, for 1.85:1, the projector's 4:3 mode zoomed will get the image within 4% of correct geometry - not very noticeable unless perhaps a circle is displayed.

What I am finding with my set up is that 1.78:1 and 1.85:1 both look the same. Geometry (circle test) is the same for both because the amount of electric squeeze Vs the optic stretch does not change. My projector has at least 5% overscan, so I am not seeing the slight difference, where there should be a slight picture width increase...

For all those oddball aspect ratios (1.66:1, 2.2:1, 2:1, etc) I guess it's best to just get a scaler and program it for all the different formats? Or are all DVD transfers from the oddball formats cropped to one of the more standard formats?

Whilst a scaler would be the best form of control, the DVD transfers them selves may not be faithful to the published AR on the pack. Again, film NOT quite 1.78:1 tends to get cropped by my set up because I choose to use 4 x 3 + lens to do 16:9., and 4 x 3 ZOOM + lens to do 12:9, so I have really just two ARs. If something "oddball" is present (the original Top Gun @ 2.00:1), I have to make the choice as to what is less offensive - slight cropping the top and bottom (wider than 16:9, but less than 21:9) or small black bars on the 16:9 mode...

Mark

I have asked this elsewhere, but since this thread is merrily zooming along, perhaps I will ask it here too. Assuming you have a constant height setup with a 16:9 projector, a lens that horizontally expands 1.33x or does 1/3 vertical compression, and a 2.35:1 screen that you use the full height for both 16:9 and 2.35:1. What do you do for the few dvd's between 1.85:1 and 2.35:1.

Since most lens' stretch the image 1.33x or compress it 1/3 .. how can you utlize the most of your 2.35:1 screen with movies between 1.85:1 and 2.35:1? Normally, you take a 16:9 image that has black bars (a 2.35:1 dvd for example) and you use the lens because 1.78:1 x 1.33 = 2.35:1 (or very close). How do you use the lens and screen for movies in 2.0:1 and 2.20:1 for instance? Would you have to calculate custom aspect ratio's so that after the lens the image is the proper aspect ratio requiring custom height and width? A 2.20:1 movie on a 2.35:1 screen that is constant height would not be the full width, of course. And movies wider than 2.35:1 would have black bars top and bottom but be full width. I am assuming that most people view 1.85:1 as is and put up with the black bars, but if you can go custom for the other in between AR's, there is nothing stopping you from using the full height of your 2.35:1 screen for 1.85:1 dvd's too.

So does anybody have experience using a constant height setup with dvd's that are 2.0:1 or 2.20:1 for example? Were you able to use the full height of your 2.35:1 screen and have the proper aspect ratio? If you did not use the lens, you would of course have black bars top and bottom and on the sides. If you accomplished this, what processor did you use? I am hoping an iScan HD+ can accomplish this.

thanx for any feedback,

:)

You have a couple of options:

1) Buy a lens that allows variable stretch. EG. Prismasonic

2) Use a fixed lens and have presets on the scaler for all ratios form 1.33-2.66+.

Vertical is more important than horizontal resolution so with constant height all the ratios use full vertical height. So even if you leave the lens on and ratios between 1.85-2.35 have slight bars left and right I doubt you'll notice much of a difference.

And there's not that many DVD's that use those formats so its not really a big deal.

Ok, fair enough. Thanx.

:)

-- this is an excerpt from promo e-mail to DWIN dealers. I thought it might have relevance to this thread. I think this essentialy does the same thing as a Runco "Cinewide" projector but a much less expensive option...Sorry about the dupe post...I didn't know how to cross reference posts (or even if that's possible!) :)



DWIN’s TranScanner Processor Fully Displays Anamorphic (2.35) DVDs.
Recently several DWIN dealers have expressed interest in so-called “super wide” projection systems that can fully display a 2.35 aspect ratio image on a similarly sized screen. You should know that DWIN has offered this capability in its projectors since 2003!

One of the many advantages of DWIN’s innovative TransVision 4 DLP projection system is the ability to independently control both the vertical and horizontal size of an image.

To fill a 2.35:1 projection screen, you may wish to consider commercially available optical lens attachments that use prisms to vertically compress or horizontally expand a picture. For example, Panamorph, Inc. manufactures a $1,495 lens fixture that optically expands a picture to fill a 2.35:1 aspect ratio screen. You simply use the DWIN Custom Image setup function to “stretch” an image vertically to eliminate top and bottom “black bars”. The lens attachment “expands” the image to normalize the aspect ratio.

Some screen manufacturers sell “variable” aspect ratio solutions with a motorized control that withdraws a shadow mask to widen the screen. You can program custom image mode in the DWIN TransVision 4 processor (as described above) to change to a custom image format as the screen shadow mask retracts.

Selling the DWIN with an anamorphic lens attachment solution can exceed the picture quality and performance of competitors systems costing two or three times the price!

A way of thinking about this is that the vertical squeeze lens does not affect the throw distance whereas a horizontal stretch lens decreases the throw.


************************************************


I found this sentence the most interesting... as I have limited throw possibilities.

-W

found this sentence the most interesting... as I have limited throw possibilities.

It means that with a vertical lens, you have to zoom the 16x9 pre lens image to the width you want 2.35 and then the lens compresses the picture vertically down.

Whereas a horiztonal lens allows you to set up the projector for the 16x9 image size you want for constant height and then add the lens which increases the with of the image for 2.35. This allows you to put the projector closer as the 16x9 constant height image is smaller in width.

It means that with a vertical lens, you have to zoom the 16x9 pre lens image to the width you want 2.35 and then the lens compresses the picture vertically down.

Whereas a horiztonal lens allows you to set up the projector for the 16x9 image size you want for constant height and then add the lens which increases the with of the image for 2.35. This allows you to put the projector closer as the 16x9 constant height image is smaller in width.

Yes I got that... that's what I like about horizontal stretch...I have a limited throw area. :)

-W

Few things to add...

The early CinemaScope films had aspect ratios of 2.66:1 and 2.55:1 (when stereo was introduced). By the time of its decline in the late 1960's, CinemaScope's aspect ratio was 2.39:1. With rare exceptions, such as two-perf non-anamorphic widescreen, almost all 2.40:1 films since 1967 have been filmed in Panavision.

Panavision's aspect ratio is 2.39:1 or 2.40:1. Neither Panavision nor CinemaScope actually use a 2.35:1 aspect ratio. The Panavision optics which replaced CinemaScope were far improved in that they eliminated what you might notice in CinemaScope films as a horizontal distortion (due to the decrease in anamorphic power as focal length decreased) during one-shot or two-shot close ups.

Therefore, older CinemaScope films are probably not the best reference material for constant height setups... and a constant height screen probably should be slightly wider, IMO, to match the far more prevalent 2.40:1 aspect ratio that is almost always and very erroneously referred to as 2.35:1 or "Scope" aspect.

and a constant height screen probably should be slightly wider, IMO, to match the far more prevalent 2.40:1 aspect ratio that is almost always and very erroneously referred to as 2.35:1 or "Scope" aspect.

Whilst film has its own set of standards, video is something else. The video anamorphic adaptors are all based on 33% stretch or compression so 1.7777777 x 1.3333333 = 2.370370369 or 2.37:1 (rounded) so is slightly wider than 2.35:1...

Mark

Ya but.????

Are they still truely 2.40:1 on the DVD's or do they shave a few pixels off each side making the DVD version of Panavision truely 2.35:1 after all??? After all, we watch DVD's, not films, with our setups. :)

-W

I would say it depends on who does the transfer.

I was watching some "scope" material the other day on a projector that has no overscan issues and there was a small pillar of black on the right hand side only so the image was not centred, yet the projector was. The DVD cover said 235, but I bet if you measured the image it was 232:1...WSR point this kind of thing out all the time...

I switched discs (another film claiming to be 235), and the image uses the full width of the panel...

Mark

okay, i'll bite. this all looks very interesting. i've read the faq along with this thread. i own an in72 and an in76. both with 92" diag 16:9 screens. my throws are very different. for my in72 it's roughtly a 14.5' throw and for my in76 it's about 12'. i'd love to try this out with one of my two setups, but i have some questions.

the prismasonic with pass thru sounds a little more interesting to me because i can leave it in place as i understand it. i'm not in the market money wise to invest in an external scalar at this point in time, so i'm hoping to do this as cheaply as posslble.

Here are my sources:
Comcast Moto 6412 DVR
Bravo D1
HTPC 6600GT DVI and ZP
Toshiba HD-A1

questions:

1. anybody using either of these two projectors with their CIH setup?

2. with the prismasonic, i will have full control with the pass thru dials and the aspect button on my INXX remote right? no other settings to mess with as long as i'm set to 16x9 on my sources right?

3. what happens to HD-DVD sources with CIH?

4. screens. hhhmmm, this could be the toughest part of all. WAF is going to be huge on this one. ideally it would be sweet to have something that could either pull down or be hung right in front of my current screen. i'm guessing i'll have to go DIY? any good threads on this? i'd absolutely love to have a little larger cinemascope style screen.

5. can someone recommend the right prismasonic for me?

tia

:)

I can help with some...

okay, i'll bite. this all looks very interesting. i've read the faq along with this thread. i own an in72 and an in76. both with 92" diag 16:9 screens. my throws are very different. for my in72 it's roughtly a 14.5' throw and for my in76 it's about 12'. i'd love to try this out with one of my two setups, but i have some questions.

Your 92" screens equate to (according to the Da-Lite screen calculator) 80.18" wide. This gives you a trow ratio of 2.17 for the in72 and 1.79 for the in76.

The Prismasonic lenses work best with higher TRs (around 1.8), so you should be right with either or both of your projectors. You will of course need a wider screen and I would suggest that a screen as large as wide as 107" (115"dia) would work best to give you a CIH...

the prismasonic with pass thru sounds a little more interesting to me because i can leave it in place as i understand it. i'm not in the market money wise to invest in an external scalar at this point in time, so i'm hoping to do this as cheaply as posslble.

The H series are designed for CIH with a pass through mode. If you were to chose their V series, then you could simply use your existing screen, but your "scope" image (the one that is supposed to be larger would in fact be smaller, and your set up would be a CIW, not CIH.

I'll let someone else help out with the other questions...

Mark

Hey Billymac and all,

Just wondering what you decided in regards to your IN72... In light of the prismasonic offer, I'm debating the H700 offer and would like to know if anybody has an input for this combination??? Currently, I'm projecting 11' from the wall with a diagonal of 84" and width of 73". Is the recessed lens an issue?

I've got a ?, I'm in the process of completing my HT and was thinking about the Mits HC 5000 with a Carada 2.35 @ 112" . projection distance is approx 15' with ceiling mount. My ? is with the projector set in cinema scope mode will it fill the screen w/o black bars when using movies that are 2.35 AR. Thanx in advance and sorry for a newbie ? ....

I've got a ?, I'm in the process of completing my HT and was thinking about the Mits HC 5000 with a Carada 2.35 @ 112" . projection distance is approx 15' with ceiling mount. My ? is with the projector set in cinema scope mode will it fill the screen w/o black bars when using movies that are 2.35 AR. Thanx in advance and sorry for a newbie ? ....

Only if you use an anamorphic lens. If you choose to ZOOM the image, you'll be projecting the black bars off the top and the bottom and wasting precious vertical pixels. It is also a PITA to realign the projector each time you change between 235 and 16:9...

Mark

When SCREEN SIZE of ADVANCED MENU is set to CINEMA SCOPE(2.35:1) in the IMAGE menu, STRETCH
cannot be selected for ASPECT.

SCREEN SIZE
You can keep the image display area within the screen by setting SCREEN SIZE in the ADVANCED MENU of IMAGE
menu according to the size of the actual screen.
When setting SCREEN SIZE to CINEMA SCOPE(2.35:1):
CinemaScope size movies are projected in the full screen.

Both entries above are out of the manual of the Mits HC 5000, are they talking about a 16x9 screen? Don't mean to be a PITA but this is new territory for me and I want something thats going to look good, the projector is pushing what I wanted to spend but I want to kinda future-proof my investment.

Thanx in advance!!

It sounds like it will crop the "scope" image back to 16:9 to "fill" the 16:9 screen. This technically is CIH as there are no black bars, but you do so at the expense of OAR.

The only way to use the full panel of the projector to display a full "scope" film is to "scale' the image. This then makes the image look tall and thin and it will not be geometrically correct. The anamorphic lens will then restore the geometry and produce an image much wider, at the same height (for HE lenses)...

Go to MY BLOG (http://cavx.blogspot.com) to see how CIH works...

Mark

Thanx for the input everyone, it's Greatly Appreciated. I'll post pix when the project is complete in a month or so. :) By the way CAVX, nice blog !!

By the way CAVX, nice blog !!

Thanks, I hope it was useful :)

Mark

So is there a chart that gives various screen sizes for a 2:35 Ratio?

In my case I have a 96x54 in screen with the PJ mounted 12 feet away. The max width I have is 13 ft or 156 inches.

So what XxX would I end up with that could work in my room.

Thanks

It would depend on where you are putting your speakers, if you have an AT screen and put them behind it then if you used the 156" wide it would be by 66" high. OR if you used the 54" height you have now, probably a good idea, it would be 127" wide.

Does anybody stretch 4:3 TV show dvd's and other 4:3 material horizontally using a video processor/dvd player and then squeeze it horizontally to make full use of the lamp and lcd panel / dlp chip etc? What lens would allow this to work best?

Does anybody stretch 4:3 TV show dvd's and other 4:3 material horizontally using a video processor/dvd player and then squeeze it horizontally to make full use of the lamp and lcd panel / dlp chip etc? What lens would allow this to work best?

No but I can stretch 4 x 3 on the 16:9 panel, then turn my lens around to form a HC and restore the geometry that way...

Mark

That is exactly what I meant. I will try that with my prisms. We need to get together and form our own lens company in order to get bulk anti-reflective coatings on our prisms :)

We need to get together and form our own lens company in order to get bulk anti-reflective coatings on our prisms :)

And there goes our DIY savings :D

Mark

There is a closed thread on the avsforum site that has a listing of what gear is available to accomlish a 2.35 setup. There hasn't been an update in some time to the listing of DVD players that support vertical stretch. Momitsu is the only one listed and their web site doesn't say that the v880, or any of the subsequent models have that capability. Is there a newer list of DVD players that have this feature?

I'm using an HTPC right now but I'd like the conenience of just popping a disc in without having to boot Windows. I also love the networking capabilities of the Momitsu v880N model but I have no idea if it can perform vertical stretch.

I am not aware of a dvd player that does the vertical stretch. Is there one?

An iScan HD+ (or maybe even the iScan HD) can do it. They aren't too expensive anymore and they are useful in that you can use it for any and all of your dvd players and other sources and it does a variable vertical stretch so that you can do all aspect ratio's that your lens can do, anything from 1.78:1 to 2.37:1.

I am not aware of a dvd player that does the vertical stretch. Is there one?

All played set to 16:9 can do the scaling - they simply output the signal "tall and skinny" when set to 16:9. The problem is if the projector will display it like that or lock up to 16:9.

There a few players that do vertical stretch including Samsung and someone even posted a photo from a Sony that not only did the scaling, but also subtitle relocation...

Mark

All played set to 16:9 can do the scaling - they simply output the signal "tall and skinny" when set to 16:9. The problem is if the projector will display it like that or lock up to 16:9.

There a few players that do vertical stretch including Samsung and someone even posted a photo from a Sony that not only did the scaling, but also subtitle relocation...

Mark


I would also like an updated list to the closed thread about the hardware, as I may consider a projector that doesn't do the stretch if I get a DVD player that does.

http://www.avsforum.com/avs-vb/showthread.php?t=537491

Thanks!

I would also like an updated list to the closed thread about the hardware, as I may consider a projector that doesn't do the stretch if I get a DVD player that does.

http://www.avsforum.com/avs-vb/showthread.php?t=537491

Thanks!

Are you (will you be) using an external scaler? To get the "scaled" image on screen, required both the source (DVD player set to 16:9) and the projector (able to display the "scaled" image) with at least 4 x 3 zoom AKA letterbox. You can not have just one...

Mark

PS you need to email Alan with your request for the updated list...

Pardon me if I have posted these questions in the wrong thread?

What are the advantages/ disadvantages of a curved screen?

What considerations must be addressed to accomplish this type of screen, ie: equipment, installation, final setup?

thanks in advance

Bill

I'm finding that having a CIH definitely make it harder to find a proper screen. I guess if I want to migrate from blackout material I have to do a build your own. My screen is about 50" x 118" for 2.37:1. Not sure if I want grey or white, but nothing too high in gain.

Pardon me if I have posted these questions in the wrong thread?

What are the advantages/ disadvantages of a curved screen?

What considerations must be addressed to accomplish this type of screen, ie: equipment, installation, final setup?

thanks in advance

Bill

The advantages of a curved screen is that the curvature can correct effects such as pincushion which may be caused by adding an anamorphic lens. Typically, the shorter the throw, the worse the pincushion becomes which is why some using lenses here don't require a curved screen.

The exact curve will be projector/lens/room dependent, so why they cost way more than flat screens...

I'm finding that having a CIH definitely make it harder to find a proper screen. I guess if I want to migrate from blackout material I have to do a build your own. My screen is about 50" x 118" for 2.37:1. Not sure if I want grey or white, but nothing too high in gain.

Are you referring to flat or curved?

Mark

Are you (will you be) using an external scaler? To get the "scaled" image on screen, required both the source (DVD player set to 16:9) and the projector (able to display the "scaled" image) with at least 4 x 3 zoom AKA letterbox. You can not have just one...

Mark

PS you need to email Alan with your request for the updated list...

Thank you for the clarification. I was hoping that if picking a projector that did not stretch vertically that there was a DVD player that would output the full vertical image to avoid an external scaler before the projector. It seems that is not the case.

The advantages of a curved screen is that the curvature can correct effects such as pincushion which may be caused by adding an anamorphic lens. Typically, the shorter the throw, the worse the pincushion becomes which is why some using lenses here don't require a curved screen.

The exact curve will be projector/lens/room dependent, so why they cost way more than flat screens...



Are you referring to flat or curved?

Mark

Probably flat. In my current setup, my screen image has only slightly distorted geometry at the edges and my next projector will be longer throw, so a flat screen will be fine.

I could probably keep my own screen frame, but I wouldn't mind trying some screen material. Not sure if I want grey or white, but nothing that has a huge gain, say 1.1 to 1.4 gain max).

Thank you for the clarification. I was hoping that if picking a projector that did not stretch vertically that there was a DVD player that would output the full vertical image to avoid an external scaler before the projector. It seems that is not the case.

There are a few DVD players that will provide the scaling, but I feel it better to find a HQ player that works with the projector.

I have the both an older interlaced Toshiba as well as the Samsung HD950 (which does full scaling with both Vertical Stretch and Horizontal Squeeze and sub-title relocation), but this player hard clips the blacks and whites (if that is important to you) so is not my primary player. The older Toshiba passes PLUGE and IMHO gives a much better picture (even if it is only SD)...

Probably flat. In my current setup, my screen image has only slightly distorted geometry at the edges and my next projector will be longer throw, so a flat screen will be fine.

I could probably keep my own screen frame, but I wouldn't mind trying some screen material. Not sure if I want grey or white, but nothing that has a huge gain, say 1.1 to 1.4 gain max).

Best to get samples from a few manufactures and watch a film :)

Mark

A dumb question, but I don't know much about 2.35:1. But I just realized that my projector can do 2.35:1 internally. It's a Mitsubishi 3000U. So, would I still need to get a lens? Will it conver all the pictures to 235:1, even if it's a 4:3?? I am so anxoius to go home and find out but just wanted to know if anyone could tell me? Thanks

Nevermind, I guess it wont' work with my HD DVD movies since the most it will accept is 576p...maybe I am not understanding this 2.35:1 correctly....bummer :confused:

A dumb question, but I don't know much about 2.35:1. But I just realized that my projector can do 2.35:1 internally. It's a Mitsubishi 3000U. So, would I still need to get a lens? Will it conver all the pictures to 235:1, even if it's a 4:3?? I am so anxoius to go home and find out but just wanted to know if anyone could tell me? Thanks

You still need the lens because you need to stretch the image back into correct proportions.

The stretch the projector gives makes everything tall and skinny whilst using the projectors full resolution and brightness.

The lens corrects the tall and skinny image so it looks correct, all the while having the advantages of the projectors full brightness and resolution.

Nevermind, I guess it wont' work with my HD DVD movies since the most it will accept is 576p...maybe I am not understanding this 2.35:1 correctly....bummer

It just means it wont stretch HD signals. In that case you'll need some other way to stretch the image. Eg, Dedicated Scaler

Thank you for the clarification. I was hoping that if picking a projector that did not stretch vertically that there was a DVD player that would output the full vertical image to avoid an external scaler before the projector. It seems that is not the case.


Yes there are there are some Samsung models that do the stretch the HD860 I believe it is and the newer one 950 Perhaps? I don't have access to the information at the moment. I bought the 860 I think it was exactly for that purpose.

Thank you for the clarification. I was hoping that if picking a projector that did not stretch vertically that there was a DVD player that would output the full vertical image to avoid an external scaler before the projector. It seems that is not the case.


I've just bought a Samsung HD860 and it does the vertical stretch required..
It is a great little player, and when set correctly gives EXCELLENT Blacks and whites through component..

I've just bought a Samsung HD860 and it does the vertical stretch required..
It is a great little player, and when set correctly gives EXCELLENT Blacks and whites through component..


Excellent thank you for the update!!! Much appreciated.

The Samsung HD-950 is also good over component (480i only). It hard clips the blacks and whites over HDMI and when upscaling - 480p, 720p and 1080i...

Mark

Okay--this totally stinks. I just ordered an HDTV (1.78:1) screen for my projector, and in hindsight would have definitely gone for a "constant height" setup. I had actually planned to make different "drops" out of black felt, dowel rods and magnets to affix to my case and adjust the "height" of the image to make a 2.35:1 screen. Thus, my 106" HDTV (52" by 92") screen would become a 39" by 92" cinemascope screen. Is this possible??? The way I understand it is my electric screen drops to the exact same point every time it opens. I can simply create this mask to hang from the projector frame when I watch cinemascope features, and viola! Problem fixed! Or is it???? What exactly happens when I project a 2.35:1 movie from my 16:9 HD projector (the projector I plan to buy is the Panny PY-AX100U). Will it not show the entire contents of a 2.35:1 film without warping? I'm totally confused here. Or will it simply display the film as a 39" by 92" image, and I'll have to adjust my screen/projector accordingly?

I had also thought about this option... a permanent, small (4" or so) felt piece hanging down from my electric screen, and I can simply drop the screen more-or-less depending on my needs (to frame the perfect setting). The electric screen I bought was the contour electrol from Da-Lite. Will I be able to stop the up and down motion of the screen at any point I wish?

Okay--this totally stinks. I just ordered an HDTV (1.78:1) screen for my projector, and in hindsight would have definitely gone for a "constant height" setup. I had actually planned to make different "drops" out of black felt, dowel rods and magnets to affix to my case and adjust the "height" of the image to make a 2.35:1 screen. Thus, my 106" HDTV (52" by 92") screen would become a 39" by 92" cinemascope screen. Is this possible???

Yes you could do that...

The way I understand it is my electric screen drops to the exact same point every time it opens. I can simply create this mask to hang from the projector frame when I watch cinemascope features, and viola! Problem fixed! Or is it???? What exactly happens when I project a 2.35:1 movie from my 16:9 HD projector (the projector I plan to buy is the Panny PY-AX100U). Will it not show the entire contents of a 2.35:1 film without warping? I'm totally confused here. Or will it simply display the film as a 39" by 92" image, and I'll have to adjust my screen/projector accordingly?

You best solution is to buy a VC lens. Panamorph have a sale for them right now. The image can be scaled (does this projector do HD?) to produce the "scaled image" - I am assuming that is what you meant by "warped" so that it removes the black bars and makes the image look tall and thin. The VC will optically compress the image to restore geometry - best of both world...

I had also thought about this option... a permanent, small (4" or so) felt piece hanging down from my electric screen, and I can simply drop the screen more-or-less depending on my needs (to frame the perfect setting). The electric screen I bought was the contour electrol from Da-Lite. Will I be able to stop the up and down motion of the screen at any point I wish?

In your case, I say get the VC lens...

Mark

Yes you could do that...



You best solution is to buy a VC lens. Panamorph have a sale for them right now. The image can be scaled (does this projector do HD?) to produce the "scaled image" - I am assuming that is what you meant by "warped" so that it removes the black bars and makes the image look tall and thin. The VC will optically compress the image to restore geometry - best of both world...



In your case, I say get the VC lens...

Mark
Or a CAVX lens - Mark I think your lens also does VC as well as HE does it not?