AVS › AVS Forum › Display Devices › 2.35:1 Constant Image Height Chat › On the cheap-How to get into the secret club?
New Posts  All Forums:Forum Nav:

On the cheap-How to get into the secret club?

post #1 of 287
1/25/07 at 2:41pm
Thread Starter 
OK guys. I'm sold.

I've read and read and I'm still lost as to how to do this on anywhere near an "economical" scale.

I want to do CIH.

I have a new AX100 (budget busted) and want to do CIH 2.35:1. My projector's capable but I need a lens. All the rif in here seems to be around Panamorph and the like costing $1000+. If that's the only deal there is, fine. I'm out. Outta my budget range.

I do see somewhat obscure threads that seem to be referencing cheaper ways of doing this with products not necessarily made exclusively for the purpose but all the conversation seems in the abstract with no specifics as to exactly what and exactly how.

My projector is shelf-mounted on a wall behind my couch. I haven't built my permanent shelf yet so there's still time to revise it and make it suitable for the purpose if I need to. Ceiling mount's out. WAY too much trouble.

Bottom line: Can this be done on the cheap, yes or no. If the answer is in the affirmative, what exactly needs to be purchased? What's the cheapest you can do it for and where do you get what you need?

I think this needs documenting not only for me but for many of us in the sub-3k forum who are looking at this forum with great interest but see if as a "boy's club" that you have to pay for with blood to be a member of and to be accepted into. Bull!

C'mon guys. Let some of the rest of us in on the party! Pretty Please.
Reply
Reply
post #2 of 287
1/25/07 at 5:17pm
Wilson, I have the same PJ as you and went with the Prismasonic H700 and I'm very pleased with the results. PJ is ceiling mounted 21' from the front wall. The screen is on order from Carada ( 130.35" x 55" ) 2.37 AR BW. The H700 on powerbuy ran a little under 1K after shipping and import tax. Do a search on DIY lense projects, some use water or oil prisms, others just good optical prisms. I looked into it and decided i'd just pony-up the cash instead of taking the risk of a botched DIY lense and I don't regret it. Hope this helps.
Reply
Reply
post #3 of 287
1/25/07 at 5:54pm
Does the Panasonic have power zoom?
Is the zoom range 1.33 or greater.

If the answer to these is yes you can do the "poor-mans" 2:35 like I'm doing right now.
You need a 2:35 screen and you then zoom out so the black bars go off the screen.
For 16:9 material you mask the sides of the screen.

scott
Reply
Reply
post #4 of 287
1/25/07 at 5:58pm
Nothing beats the lens approach though...

Mark
Reply
Reply
post #5 of 287
1/25/07 at 6:53pm
The AX100 has 2.0x zoom so all you have to do is ZOOM... and it costs nothing... plus, it will give you none of the artifacts of an anamorphic lens.

For 16:9 images, you will use full panel 1280 x 720.
For 2.35 images, you will use 1280 x 544.

Granted, you are losing resolution, but I'm sure you will be pleased with the result as long as you can't see screen door. otherwise, the only other way to do it is spend several hundred $$$ on even an entry level lens.
Reply
Reply
post #6 of 287
1/25/07 at 6:54pm
Quote:
Originally Posted by scottyb View Post

Does the Panasonic have power zoom?
Is the zoom range 1.33 or greater.

If the answer to these is yes you can do the "poor-mans" 2:35 like I'm doing right now.
You need a 2:35 screen and you then zoom out so the black bars go off the screen.
For 16:9 material you mask the sides of the screen.

scott

That's it...all you need to join the "Constant Image Height" club. Not so bad, eh? The "Added Brightness" or "Full Vertical Panel Resolution" clubs are a little more exclusive, but you can certainly achieve the cinematic (primary, for me) goal this way.
Reply
Reply
post #7 of 287
1/25/07 at 6:59pm
May I suggest the link CAVX sig... DIY lens, if your projector does the stretch it fits anyones budget... then you can use your full panel. It has been well documented on how to make your own lense, I've got mine already just need the projector
Reply
Reply
post #8 of 287
1/25/07 at 7:03pm
Thread Starter 
Quote:
Originally Posted by roar View Post

May suggest the link CAVX sig... DIY lens, if your projector does the stretch it fits anyones budget... then you can use your full panel. It has been well documented on how to make your own lense, I've got mine already just need the projector

Thanks EVERYone. GREAT information here IMO.

Is the DIY lens a forum on AVS or is it somewhere else? Surely a link to a DIY forum is permissable here.
Reply
Reply
post #9 of 287
1/25/07 at 7:13pm
I bought a Panamorph u85... I think it's reasonably priced in a power-buy situation, so keep your eyes peeled.
Reply
Reply
post #10 of 287
1/25/07 at 7:45pm
Quote:
Originally Posted by Jagercola View Post

I bought a Panamorph u85... I think it's reasonably priced in a power-buy situation, so keep your eyes peeled.


If a U85 works, there's a couple for sale in the classifieds here at AVS.

scott
Reply
Reply
post #11 of 287
1/25/07 at 8:31pm
Quote:
Originally Posted by pocoloco View Post

The AX100 has 2.0x zoom so all you have to do is ZOOM... and it costs nothing... plus, it will give you none of the artifacts of an anamorphic lens.

For 16:9 images, you will use full panel 1280 x 720.
For 2.35 images, you will use 1280 x 544.

Granted, you are losing resolution, but I'm sure you will be pleased with the result as long as you can't see screen door. otherwise, the only other way to do it is spend several hundred $$$ on even an entry level lens.

Granted indeed

With the lens not only can you get full panel 1280 x 720 for 16:9 but also get full panel 1280 x 720 for "scope" as well.

In my case I choose to leave the lens in place all the time so I don't use the full horizontal rez for the smaller ARs of 16:9 and 4 x 3.

I do however use the full vertical rez all the time, and trust me, our eyes are way more sensitive to vertical rez than horizontal so the lens makes a huge difference...

Mark
Reply
Reply
post #12 of 287
1/25/07 at 8:32pm
Quote:
Originally Posted by Wilson-Flyer View Post

Thanks EVERYone. GREAT information here IMO.

Is the DIY lens a forum on AVS or is it somewhere else? Surely a link to a DIY forum is permissable here.

A little here: http://www.avsforum.com/avs-vb/showt...&&#post8301109

And a LOT here (you can start reading somewhere in the middle, when the revelation about prismatic trophies gets introduced): http://www.diyaudio.com/forums/showt...0&pagenumber=1 (looks like the site is down right now, try later)
Reply
Reply
post #13 of 287
1/26/07 at 8:43am
page 62 to be exact
Reply
Reply
post #14 of 287
1/26/07 at 12:57pm
Especially if you like DIY. It has been a great project, and the results for the price--can't be beat...
Reply
Reply
post #15 of 287
1/26/07 at 2:05pm
Quote:
Originally Posted by CAVX View Post

Granted indeed

With the lens not only can you get full panel 1280 x 720 for 16:9 but also get full panel 1280 x 720 for "scope" as well.

In my case I choose to leave the lens in place all the time so I don't use the full horizontal rez for the smaller ARs of 16:9 and 4 x 3.

I do however use the full vertical rez all the time, and trust me, our eyes are way more sensitive to vertical rez than horizontal so the lens makes a huge difference...

Mark

I agree with everything you said. But he's looking for constant height on the cheap, and that's what zooming is. If I had an unlimited budget, I'd get an ISCO III and be done with it.

That's not to say that anamorphic lenses don't have their own issues. Yes you get to use the entire panel and get some increase in light output, but you'll also get geometric distortion, chromatic aberrations, focus uniformity issues... depending on the pj throw and lens of course. But I've seen high-end Runco setups that still have these issues. Basically, it's about trade-offs and what's more acceptable to you. Resolution is not the ultimate determiner of PQ and actually ranks pretty low IMO.

I've owned panamorphs and prismasonics in the past and to me zooming results in a overall more refined picture... because the best lens is no lens. Now if I upgrade to a long throw pj and get and ISCO 3, maybe I'll speak differently, but that's a lot of dough.

Realistically, my next pj will be 1080p. I'll have 1920x1080 for 16:9 and 1920x817 for 2.35 if I end up not getting a lens. Zooming seems to be a more acceptable for 1080p projectors because even for 2.35 content, I'm still in HD category and as long as I don't see screen door, I'll be happy. If I have $5k to burn, I'll be the first to buy an ISCO 3.
Reply
Reply
post #16 of 287
1/26/07 at 9:36pm
Quote:
Originally Posted by pocoloco View Post

Resolution is not the ultimate determiner of PQ and actually ranks pretty low IMO....Realistically, my next pj will be 1080p.



Mark
Reply
Reply
post #17 of 287
1/27/07 at 12:35pm
Quote:
Originally Posted by CAVX View Post



Mark

What's so confusing about my post??? Just because I think resolution ranks low in determining picture quality doesn't mean that I don't want high resolution.

If push comes to shove, I'm willing to sacrifice resolution over other picture characteristics. But that doesn't mean I don't want 1080p. Even for constant height, of course I would love to use the full panel, but not at the expense of other picture characteristics. That's why I would say if I had the cash, I would try an ISCO 3.
Reply
Reply
post #18 of 287
1/28/07 at 4:40am
The purpose of CIH when using an anamorphic lens is to capitalize on the full vertical rez of the projector. Why have 1080 vertical pixels and not use them all. Sure 810 is more than the current 720 projectors, but if you have 1080, why not use them all?

Mark
Reply
Reply
post #19 of 287
1/28/07 at 5:08am
Quote:
Originally Posted by CAVX View Post

The purpose of CIH when using an anamorphic lens is to capitalize on the full vertical rez of the projector. Why have 1080 vertical pixels and not use them all. Sure 810 is more than the current 720 projectors, but if you have 1080, why not use them all?

Mark

Small Budget!!!
Reply
Reply
post #20 of 287
1/28/07 at 11:33am
Thread Starter 
Thanks guys for ALL of your help. I'm working with Mark on a solution that I think is gonna suit my situation perfectly.

Again. Thanks and props. this thread has been exactly what I wanted to know.
Reply
Reply
post #21 of 287
1/28/07 at 7:39pm
Quote:
Originally Posted by CAVX View Post

The purpose of CIH when using an anamorphic lens is to capitalize on the full vertical rez of the projector. Why have 1080 vertical pixels and not use them all. Sure 810 is more than the current 720 projectors, but if you have 1080, why not use them all?

Mark

Because to me, the increase in resolution does not justify the artifacts introduced by an anamorphic lens... and SMALL BUDGET.

I don't know why you persist in debating me so much on this. .. maybe because of your financial interests with your aussiemorphic lens??? All I'm saying is that there are 2 routes to constant height: zooming and anamorphic lens. Each route has it's pros and cons and it's up to each individual to weigh them out and decide for themselves. The original poster asked what was a cheap way to do constant height and I responded by suggesting zooming and the associated benefits.

Again, I'll outline them here:

Anamorphic lens:
PROS
- able to use full vertical resolution
- increase in light output
CONS
- overall softer picture
- potential degrees of geometric distortion
- potential degrees of chromatic aberration
- potential focus uniformity issues
- costs money
- possibly need external scaler

Zooming:
PROS
- no additional picture artifacts
- no cost
CONS
- none of the PROS of using a lens
- potential screen door
- not resolving full 1080 lines

There you have it.
Reply
Reply
post #22 of 287
1/28/07 at 8:35pm
Quote:
Originally Posted by CAVX View Post

The purpose of CIH when using an anamorphic lens is to capitalize on the full vertical rez of the projector. Why have 1080 vertical pixels and not use them all. Sure 810 is more than the current 720 projectors, but if you have 1080, why not use them all?

Mark

But you don't really get 1080 lines of resolution. There are only (about) 810 lines recorded on the disk, and scaling these up in the projector doesn't create any more actual detail in the picture. If anything the process of scaling up and then down is bound to lose a bit (it would be interesting to see if this could be detected with a resolution chart).

So this is one more vote for the zooming method. I used to call it the "poor man's" CIH, but assuming you have enough lumens and SDE is not a factor, I don't think it has any disadvantages.
Reply
Reply
post #23 of 287
1/28/07 at 8:47pm
Quote:


Anamorphic lens:
PROS
- able to use full vertical resolution
- increase in light output
CONS
- overall softer picture
- potential degrees of geometric distortion
- potential degrees of chromatic aberration
- potential focus uniformity issues
- costs money
- possibly need external scaler

Zooming:
PROS
- no additional picture artifacts
- no cost
CONS
- none of the PROS of using a lens
- potential screen door
- not resolving full 1080 lines

There you have it.

I can't agree with a softer picture and loss of PQ due to distortions. This only happens if you have a very poor quality lens thats not setup correctly and not enough throw distance.

Another CON for not using a lens is light spill which is quite substantinal and annoying if not masked properly. The lens gives the whole setup a finished feel while gaining the extra PQ.
Reply
Reply
post #24 of 287
1/28/07 at 8:50pm
Quote:


But you don't really get 1080 lines of resolution. There are only (about) 810 lines recorded on the disk, and scaling these up in the projector doesn't create any more actual detail in the picture. If anything the process of scaling up and then down is bound to lose a bit (it would be interesting to see if this could be detected with a resolution chart).

So this is one more vote for the zooming method. I used to call it the "poor man's" CIH, but assuming you have enough lumens and SDE is not a factor, I don't think it has any disadvantages.

Have you had the chance to see a 2.35 setup with a lens? I guarentee you will notice the extra resolution used on the projector end due to scaling. Even though it may not be there on the original disc using the full vertical rez of the projector panel helps quite a bit especially with perceived smoothness of the image.
Reply
Reply
post #25 of 287
1/28/07 at 9:07pm
Quote:
Originally Posted by Tukkis View Post

Have you had the chance to see a 2.35 setup with a lens? I guarentee you will notice the extra resolution used on the projector end due to scaling. Even though it may not be there on the original disc using the full vertical rez of the projector panel helps quite a bit especially with perceived smoothness of the image.

I admit I haven't done the comparison myself, but with a 1080p projector I imagine you would have to be sitting very close to see any improvement in smoothness. Can I ask what your viewing distance is (in screen widths)? I sit at 1.4 screen widths for 2.35:1 material, and I'm really not convinced an extra lens would be worth it for me, even though I'm very picky about image quality.
Reply
Reply
post #26 of 287
1/28/07 at 9:33pm
Quote:


I admit I haven't done the comparison myself, but with a 1080p projector I imagine you would have to be sitting very close to see any improvement in smoothness. Can I ask what your viewing distance is (in screen widths)? I sit at 1.4 screen widths for 2.35:1 material, and I'm really not convinced an extra lens would be worth it for me, even though I'm very picky about image quality.

I sit 1.2x widths with a 720p projector. Most would say it's too close but the lens does help with sitting closer.
Reply
Reply
post #27 of 287
1/28/07 at 11:20pm
Quote:
Originally Posted by Tukkis View Post

I guarentee you will notice the extra resolution used on the projector end due to scaling. Even though it may not be there on the original disc using the full vertical rez of the projector panel helps quite a bit especially with perceived smoothness of the image.

Agree 100%. Well said Tukkis...

Mark
Reply
Reply
post #28 of 287
1/29/07 at 5:04am
Quote:
Originally Posted by Tukkis View Post

I sit 1.2x widths with a 720p projector. Most would say it's too close but the lens does help with sitting closer.

I definitely agree that reducing the pixel size will make a noticable difference for 720p at 1.2x, but the jump from 720p to 1080p will make a bigger difference, and it's at that point I question whether the anamorphic lens adds value.

I guess one way to test this is to sit at 1.8x with your current 720p setup and then compare the result with and without lens.
Reply
Reply
post #29 of 287
1/29/07 at 12:30pm
Quote:
Originally Posted by kriktsemaj99 View Post

I definitely agree that reducing the pixel size will make a noticable difference for 720p at 1.2x, but the jump from 720p to 1080p will make a bigger difference, and it's at that point I question whether the anamorphic lens adds value.

I agree that 1080p should make using a lens less necessary from almost all reasonable seating distances (as long as brightness is adequate on the given screen size). At the very least it should be even more important to use a quality lens and set it up correctly. It seems to me that since 1080p projectors inherently have very high quality lenses to fully resolve all the resolution, it's even more likely that adding a low to mid-level lens would do more harm than good.
Reply
Reply
post #30 of 287
1/29/07 at 1:37pm
You know, when I first got my projector (AE700) last year and started reading about 2.35:1 and what it took to do it "correctly" I decided that I would try the 'zoom method'. After seeing how much light spilled onto my wall because of the geometrically incorrect sizing of the picture I could/will NEVER go back to zooming. I am by no means a videophile 'purist' who despises anyone who dares to do it "on the cheap", but for me the decision was easy. I just can't imagine busting my butt to get my HT just the way I wanted, and spending as much money as most of us do on this hobby to all of a sudden cheap out on a lens. But to each his own
Reply
Reply
New Posts  All Forums:Forum Nav:
  Return Home
AVS › AVS Forum › Display Devices › 2.35:1 Constant Image Height Chat › On the cheap-How to get into the secret club?