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Discussion Starter · #1 ·
I am installing a 75U and contemplating screen sizes and aspect ratios.


My wife and I agree that 92" wide is great for 1.78-2.35:1 aspect ratios, but would like 4:3 material to be smaller to account for image height. Thus, we are strongly leaning to a 92x52 screen.


We intent to view 4:3 in the S4:3 mode (the zoom of the 75 U wont go small enough to vary between 16:9 and full field 4:3).


Questions:

1. Can the 75U digitally zoom down 4:3 mode in relatively fine increments so we can use close to native resolution when zoomed optically down in 4:3 (i.e., to zoom a little more)?


or


2. For DirectTV and other S-video sources, does the loss in resolution running in 4:3 even matter in terms of visual quality as there are more pixels in this mode than in the source material anyway?


(disregard brightness issues)
 

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I don't think there is a control or feature to incrementally zoom a picture down in size.


One thing you could try is setting the resize option to "NO" so that the projector displays images in their native rate (ie if fed a 800x600 image, it'll show an image at that size, instead of scaling up to 1024x768). Then if this image is smaller than you need, you the manual zoom to make it bigger.
 

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Quote:
Originally posted by dxb


Questions:

1. Can the 75U digitally zoom down 4:3 mode in relatively fine increments so we can use close to native resolution when zoomed optically down in 4:3 (i.e., to zoom a little more)?
No it cannot, this is drive me crazy. I have to move my PJ when I switch between 16:9 and 4:3.

Quote:
Originally posted by dxb


2. For DirectTV and other S-video sources, does the loss in resolution running in 4:3 even matter in terms of visual quality as there are more pixels in this mode than in the source material anyway?
There is a major loss in quality from S-video sources, especially with Satellite TV.
 

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Discussion Starter · #4 ·
I typoed;


I meant does it lose apparent resolution in S4:3 compared to 4:3 zoomed down. I did get the 75u (love it); and have found that the DirecTV quality is soo low it's a 'who cares'. S4:3 is fine.
 

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I am thinking about purchasing the 75U. I do not have a manual for a 75U. What does this S4:3 mode exactly do and what are the tradeoffs of using it ? From what I read in other posts - it allows you to view a 4:3 image "inside" the boundries of a 16:9 screen. But how does it do this ? What does the "S" stand for in S4:3 mode ? And what does it sacrafice over regular 4:3 mode on the 75U ?
 

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The s in s4:3 stands for small. With the s4:3 mode, a 4:3 source is displayed in the center of a 16:9 screen. With standard 4:3 mode, the 4:3 picture would be too large for a 16:9 screen, exceeding the screen on the top and bottom. The benefit of using s4:3 with 16:9 screen, is it first allows you to have the larger screen for your 16:9 HDTV and DVD's. Second, when viewing 4:3 material (mostly low res NTSC), the image will be smaller and therefore the graininess of a poor res broadcast won't be as noticable.


Most people op for a 16:9 screen, because they have limited real estate for screen height. You can fit a much larger 16:9 screen in the same height that you could fit a 4:3 screen. If you had plenty of height, then I would recommend a 4:3 screen, and using horizontal masking for all different aspect ratios. With the 16:9 screen and s4:3 mode, you will need horizontal masking for the different widesreen ratios, and vertical masking when showing 4:3 (curtains on the sides).
 

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So let me see if I interpret this correctly. What I would like to do if I decide on the 75U - is use the sheet of Parkland plastic that I have - a 4' X 8' sheet. Create a 16:9 aspect ratio out of it by cutting it down to approx. 4' X 7.1' giving an approximate 98" Diagonal. Then place the 75U at the proper throw distance for a 16:9 ratio for a 98" Diagonal picture (which I'm not sure what that would be - can someone provide that link ?). Then for 4:3 source - keep the projector where it was for 16:9 viewing and set the 75u to this S4:3 mode and get a 4' high picture by approx. 5.33' wide. Does this sound right ? will this work for me ?
 

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By George, I think he's got it :)


As far as the throw calculation, for some reason ProjectorCentral doesn't have it for the 75u. I tried to use the calculation in the book for a 16:9 screen and it was way off.


Search for the 75u/711 Screen thread that shows alot of members setups including screen size and projector distance. You should find something close in there.


Edit: I did it for you

http://www.avsforum.com/avs-vb/showt...hreadid=142487
 
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