2.35 Constant Height Faq - Page 8

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...


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 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 ? ....

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 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 !!

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?

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

And there goes our DIY savings

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.

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!

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.

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

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.

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).

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)...


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