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Newbie Question for CIH 2:35 Screen

post #1 of 16
6/26/07 at 4:21pm
Thread Starter 
Ok I will show my inexperience here. Just purchased the HD 1000U about 2 weeks ago, no decision on screen yet but I am pretty sure I want to go with 2:35 and masking with curtains or something. Here go the questions.

1) My screen is going to be Wilsonart DW, painted with silver. I am zooming in a bit to get viewable screen down to 61" height ( that is as tall as DW comes in), this gives me 108"W screen when projector is set 16:9 aspect. I should state that when in max zoom the blue screen (no signal) is 67"x119". Here's where I get lost. When I put in a DVD in 2:35 and zoom out to the max my heigth goes from 61" to 53" but the width goes from 108" to 119" like I thought it would and should. My question is, I thought when I zoomed out the heigth should stay at 61" and not go down to 53", what happen to the "constant heigth" with 16:9 and 2.35? When I put the 2:35 movie in I did not change the aspect ratio on the projector from 16:9 to 2:35, if I do the picture even gets smaller? What am I doing wrong here? Should I use the the zoom1, zoom2, or stretch functions to enlarge the 2:35 picture? As you can see I am totally lost and any help you guys could give would be greatly appreciated. Thanks so much.

Golffnutt
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post #2 of 16
6/26/07 at 5:01pm
When "zooming" I assume that you are just using the projector's zoom function to enlarge the picture right? You shoud not be using the zoom function on your DVD player for this. I don't know the projector but it will either have manual zooming (you turn a ring around the lens) or it may have electronic zoom. When you mentioned "zoom1" "zoom2" or "stretch" function it sounds like you are using the wrong controls. There will be no specific setting for zoom that you use. It is a complete "eyeball" thing where you use the projectors zoom function to enlarge the image until the black bars on the top and bottom of your 2.35 image are off the screen. Hope that makes sense.
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post #3 of 16
6/26/07 at 5:16pm
With a constant height 2.35:1 screen if it is 61 inches high then it would have to be 143"wide.
your other choice is if you want to keep the width you currently have, 119" then your screen would be 119 wide by 51" high. that is how this works.

If you graduate to an anamorphic lens instead of just zooming then you will use letterbox on your projector which will stretch your image vertically then the lens will stretch it horizontally if it is a HE lens.
There are other things to consider and understand, like your throw ratio etc. but this is how the screen size works.
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post #4 of 16
6/26/07 at 5:51pm
Thread Starter 
Thanks guys for your replies. As mentioned in original post my total viewing area is 67x119 when the zoom is maxed out (the zoom around the lens that is).

When I zoom in to 61" high which is the max height I can use with Wilsonart DW laminate (only comes in 61x120) that reduces the width to 108. When I put in a 2:35 movie and zoom out with lens zoom the height goes to 53 and width to 119. If this is the case then I would have to use masking on top and sides, makes no sense. Still lost.
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post #5 of 16
6/26/07 at 6:00pm
What you are missing is that you choose a constant height that works for you for your 16:9 viewing, then you take that height time 2.35 and that gives you the width of your screen. THAT is the size you make your screen. then if you watch 16:9 it would be that height but 33% narrower so you use SIDE masking if you want to.
when watching 2.35 you zoom to fit the entire screen which forces the black bars off the screen. If you are using a lens and a scaler then the scaler eliminates the black bars by stretching the picture tall and and the lens stretches it back out to fit the screen but you are not using your projectors entire panel to show picture not part of it to project black bars. with the zoom method you are still projecting the black bars but you have zoomed them off the screen where you cannot see them.
does that help?
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post #6 of 16
6/26/07 at 6:17pm
Thread Starter 
MCCall that does help but here's my dilemma with your formula. My screen will only zoom out to a max of 119"x67" so if I set my height to 61" there is no way I can get a 143" wide screen for 2.35 because it will not zoom that far out so I guess this means I can not use a CIH?
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post #7 of 16
6/26/07 at 6:35pm
What McCall is saying is that the 16:9 image based on 61" is 108.58", and a "Scope" image would have to be 144.57" (based on 2.37:1) to be the same height. You've already stated that you can not zoom that far, but you could if you employed an anamorphic lens, you could quite easily do this.

Your only other option is to reduce the screen height...

Mark
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post #8 of 16
6/26/07 at 6:36pm
well in the first place 143 is a darn big screen much bigger than most people here use and it takes a lot of projector to do it justice. The fact you can only zoom to 119 is very similiar to mine I could only zoom to 116 with my throw of 16'.
I decided on a 120" x 51" 2.35.1 SMX acoustically transparent screen and I got a UH380 anamorphic lens, with the lens you use NO zoom or very very little and you let the scaler which can be in the projector, dvd player or a stand alone unit and the lens to get the picture to the full 120" size.
You can certainly go with a 50 x 119 screen and have a 50" CIH.
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post #9 of 16
6/26/07 at 6:39pm
Good point McCall - whist size matters (or what you do with it ), you still need to be able to light the thing, or it defeats the purpose of going that big...

Mark
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post #10 of 16
6/26/07 at 6:41pm
Thread Starter 
Ok think I got it now. I am set on the 61"H for 16:9 so I will have to be content with the 51"H on 2.35 for now. If I did buy the A Lens for the 143"W 2:35 what kind of PQ do you think I would get with the HD 1000U, in other words is it really worth it to buy the A lens, by the way how much is a good quality A lens? Thanks buys you have been a tremendous help.
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post #11 of 16
6/26/07 at 6:57pm
depends on the lens. there are two types HE and VC but I did not want to get into that until you understood the basic concepts of screen size etc.

There may still be a power buy going on for the UH380 for $1895 I think it should be listed at the top of the forum section here if it is still on, the normal price on that one can be seen at the Panamorph.com site. there are also the Prismasonic brand lenses similiar in reg prices. then there are some even more expensive brands.
Then depending on the projector you have and if it does the necessary vertical stretch needed or if your DVD player does it, otherwise you may need a scaler and they can run from 500 to thousands.
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post #12 of 16
6/27/07 at 4:45am
Thread Starter 
WOW, don't think CIH is worth that to this ole boy. Thanks for that info.
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post #13 of 16
6/27/07 at 8:20am
Quote:
Originally Posted by golffnutt View Post

WOW, don't think CIH is worth that to this ole boy. Thanks for that info.

Just so you know there are also do it yourself lens options that are far less expensive for that part of the equation. It was late when I posted and I had not even thought about that possiblity.
Still maybe not for you, but just wanted you to know it is possible.
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post #14 of 16
6/27/07 at 8:28am
Thread Starter 
Thank you McCall for that info. Any idea where I may find some info on these? Thanks again for your help.

Golffnutt
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post #15 of 16
6/27/07 at 9:22am
Quote:
Originally Posted by golffnutt View Post

Thank you McCall for that info. Any idea where I may find some info on these? Thanks again for your help.

Golffnutt

It's a subforum at the top as you open this forum...called DIY C.H.


http://www.avsforum.com/avs-vb/forum...ysprune=&f=174
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post #16 of 16
6/27/07 at 11:10am
Thread Starter 
Thanks Rboster.
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