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and so the first of my many stupid questions to come as we begin contruction on a theater room in a new home construction. my other thread describes specifics of room, but essentially 23.5 x 16 feet. thinking about a 110" (possibly 120") screen. question is what is the benefit of a 2.35:1 screen ratio? room will be 1/3 movies, 1/3 broadcast tv and 1/3 video gaming. i want a 16:9 screen don't I? then just use some kind of masking for 2.35:1 and 2.40:1 content?


or am i offbase? (ENTIRELY possible)
 

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Quote:
Originally Posted by SoonerDoc /forum/post/0


and so the first of my many stupid questions to come as we begin contruction on a theater room in a new home construction. my other thread describes specifics of room, but essentially 23.5 x 16 feet. thinking about a 110" (possibly 120") screen. question is what is the benefit of a 2.35:1 screen ratio? room will be 1/3 movies, 1/3 broadcast tv and 1/3 video gaming. i want a 16:9 screen don't I? then just use some kind of masking for 2.35:1 and 2.40:1 content?


or am i offbase? (ENTIRELY possible)


A lot of people don't bother to mask when they show 2:35 material on a 16:9 screen. They just live with the black bars on the screen. Myself included.


My problem is that when you show a 2:35 on a 16:9 screen the image gets kind of small so you really need to start out with a little larger 16:9 than you might originally thought.


We didn't and now I'm comtemplating going 2:35 and all that means to do it right. When I do, it will be the same height as the existing 16:9 I have now.
 

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The other option is a constant image height screen. Both 16:9 and 2.35:1 aspect ratios would have the same height, but the 2.35:1 image would be wider than the 16:9. I don't believe all projectors are capable of projecting constant image height.
 

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I'm going for 2:35 aspect screen and then masking for 16:9. I want to do something similar to IWISHIWASFLYING. He has panels on a kind of rail that slide into his screen wall when he needs to 2:35.


Like Big said your 2:35 image on a 16:9 screen will be smaller and to get the best of both worlds you want to get a constant height screen.
 

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Visit the CIH chat section and view the pictures of people who have 2.35:1 screens. There is more to CIH than just the 2.35:1 aspect screen however. But it will explain things better and then you can decide what is most important to you.

I think given the mix you mention that 16:9 would DO alright for you.


I don't see a lot of point in getting a 2.35:1 screen if you are not doing the whole CIH thing. [ anamorphic lens, possible scaler ] Just stick with 16:9. But for those of us that use the theater as a Movies theater almost exclusively then 2.35:1 is certainly a fabulous Cinema experience.
 

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Quote:
Originally Posted by McCall /forum/post/0


Visit the CIH chat section and view the pictures of people who have 2.35:1 screens. There is more to CIH than just the 2.35:1 aspect screen however. But it will explain things better and then you can decide what is most important to you.

I think given the mix you mention that 16:9 would DO alright for you.


I don't see a lot of point in getting a 2.35:1 screen if you are not doing the whole CIH thing. [ anamorphic lens, possible scaler ] Just stick with 16:9. But for those of us that use the theater as a Movies theater almost exclusively then 2.35:1 is certainly a fabulous Cinema experience.

How do you determine if your PJ will handle Constant Height? Would that be in the manual? I have an older Panny 500, and I'm guessing it won't do Constant Height?
 

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Good comments above. My (long) take:


I'm in the same boat: 16x21 foot room, planning the screen.


If you build a 16x9 screen, normal HD broadcast content and games would be fine. 2.35:1 movies would have black bars top/bottom. Not that big a deal. Probably not worth having special masking for.


However, to some folks that is backwards. Big cinematic movies (the type which typically have 2.35:1) should be the BIGGEST thing you watch, not the smallest.


Solution: 2.35:1 screen constant-image-height setup. Now 16x9 content will have black bars on the sides, and 2.35:1 movies will look big and impressive.


Unfortunately, the screen is the easy part. You need to get your 2.35:1 movie filling the screen.


One possible way would be to zoom your picture bigger. The black bars would still be there, but would be off the screen on masking material above and below. Don't know how common this is.


The more expensive and more talked about method: put a video processor between your source and your projector. Use that processor (scaler) to stretch the 2.35:1 movie vertically so that it fills the 16x9 projector panel. If you now project normally (16x9 size), everyone will look tall and skinny. Then you put a lense or prism in front of the projector to stretch the 16x9 picture to 2.35:1.


The advantage of the latter route is that you are using all the pixels in the projector and therefore potentially have a sharper and brighter image.


The disadvantage is that the scaler and lense can be expensive ($500-$4000 for the scalar, similar for a purchased lense). Also, with 16x9 material, you either need to slide the lense out of the way and turn of the scaler function, or have the scaler squish the 16x9 material to have the right aspect ratio with the lense in place.


A home theater PC may be able to work as a scalar (definitely for DVD's, not sure on HD content). The scalers in projectors should actually be able to handle this quite easily, but it doesn't seem to be a common option. CIH is a niche and they don't think to program that into the internal scalers.


Some folks do DIY lenses made out of prisms. Sounds like they can put them together for a few hundred $, but I don't know the quality.


Check out the CIH discussion forum for more, but that should get you grounded.


My plan: I'm leaning towards putting in a 2:35:1 screen, but masking it down to 16x9 for now (hide the wideness with black curtains or something). For now, movies will have black bars. Then if I get the bug, I can buy the other equipment and not have to redo my screen wall.
 

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Quote:
Originally Posted by tonybradley /forum/post/0


How do you determine if your PJ will handle Constant Height? Would that be in the manual? I have an older Panny 500, and I'm guessing it won't do Constant Height?

Any projector will do constant height with an external scaler and a lense.


The real question is whether the panny will do the vertical stretch for you (the scaler part) and save you the expense of an external scaler. Check the CIH forum, I'm betting an FAQ over there will tell you if your pj will do the stretch. Or a quick question will get you answers.
 

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They way I understand CIH theory, it's not so much as to whether you projector "supports" it, but about the quality and brightness of the image once you have sent the image through a scaler and lens prism to make full use of the projector image. Anyway, read the CIH faq in the CIH forum for all of the brainmelting details.
 

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Don't look for your manual or even your projector salesman to mention CIH, they don't seem to know such a thing exists.

and I agree with the Mind melting details comment LOL it took me about 3 weeks and a lot of questions and misunderstandings to finally "Get It" but boy was it worth it.


The zoom the black bars off the screen method is the Poor man's method or the Ghetto method, or so it is nicknamed. whether you have that much zoom depends on your projector and your throw distance.


The preferred way is to use an anamorphic lens, [there are two different types, Vertical compression and horizontal expansion] with either you need to vertically stretch your image where the people look tall and thin then the lens adjusts the geometry and gives you the 2.35:1 picture minus the black bars, but now using all the pixels in your projectors panel rather than losing some to the projection of black bars.


as to light loss, there is some because you are spreading over a larger area, at least with the HE type lens, but it is not noticible on the screen in fact the result is a huge WOW factor.
 

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I have a 16:9 110" screen in a 15'x22' room and love it. I do mostly HDTV and Video games, with some movies though. So the only thing that has black bars is the movies. Due to the way the room is contructed I could not get a wider screen. Because of this if I had gotten a 2.35:1 screen, then my HDTV and Video Game projections would have been smaller.


My suggestion is get the widest 16:9 screen you can as long as the height is not a limiting factor. That way you get the largest viewable area for everything.


After watching my HDTV for a while if I switch to movies, the picture does look a little small, but I get over that in about 10-15 seconds (About when I no longer notice the black bars).
 

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Tony - if you do, just know that you can always upgrade with a lense and scaler down the road. As demand increases for these things there are bound to be some more affordable solutions available. At least that's what I keep telling myself.
 

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That's my take as well. The scaler I can handle. I'll have a home theater PC at some point and I figure I can use that.


The lense is the issue. I'm hoping volume starts pushing the prices down.
 

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I had been comtemplating a 2.35 and then I masked out some screen sizes on my wall. For me the perfect width is going to be about 100". So I took that starting figure and realized that a 100" 2.35 screen would be about 42.5" tall. I also realized, that I would still have plenty of vertical room, so instead I am going to get a 100x56" or 114" diagonal 16x9 screen.


I realize that scope movies will wind up smaller than non-scope, but they will still be the same width if I went with the 2.35 screen, but now I also have much more area I can use for HDTV and Sports.
 

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If you are width limited (either by the screen wall width or by seating distance/head turning physics), than going 'constant image width' instead of 'constant image height' makes sense.


It seems to me there are really two separate parts to the CIH 'philosophy':


1) get as big a picture as you can on wide screen movies.


2) don't waste valuable projector panel resolution and valuable lumens on black bars below/above wide screen movies.



If you go with the widest screen you can fit, you are meeting #1.


#2 is only a philosophical issue unless you have brightness issues or you are sitting close enough relative to screen size that you can notice higher resolution.


If your picture is big, bright, and sharp, you are set.
 

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One other option not discussed much is one I used. Constant area.

I have a 2;00 aspect ratio screen. 2;35 movies are larger than on a 16:9 screen and 16:9 movies are larger than they would be on a 2:35 screen. Your projector doesn't need much zoom.

The only negative is you have black bars on both format but they are VERY small.

You can also have a simple masking system for them, which I'm working on. I will say the bars are much less noticable than the wider ones.


scott
 
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