I'm working on building out a new home theater setup. Room is completely empty, not even walls -- just concrete all around. The wall that will have the screen is 16' (192") wide and 9.5' (114") high. Seating distance in optimal (middle) row will be about 16' - 20' from the screen.
I should say that I'm a relative newbie to these things, so feel free to educate me if I'm getting something horribly wrong here.
I figure that the screen can be no closer than 16" from the concrete ceiling, which gives enough space for building a wood / drywall ceiling, including acoustic and aesthetic treatments, and some space for trim around the screen. I'll need about 3" to build a floating floor. People sitting in the middle-row seats will have their eyes about 48" off the floor. Optimal screen height (based on: Eye Height - Screen Height / 3 = Screen Bottom to Floor distance) puts the screen about 21" off the floor. I could maybe fudge this a little, and move a larger screen 6" lower so it's 15" off the ground.
From what I understand, I have essentially three options:
(1) CIH w/Zoom, left/right masking. Native screen AR is 2.4:1. Now, this is key: I assume that in the zoom setup, I will *still* need top/bottom masking, so small amount of light from the projector's black bars don't bleed onto the surrounding wood cabinet. Consequently I need to in-effect be able to project a full 1.78:1 image onto my screen+masking combo. I am height constrained in my room, to a screen+masking height of about 81". Even that would be pushing it, but this gives me a screen width of 144" = 12 feet. Fits in the width of the room for sure. The image height for 2.35:1 content would be 60". Because it's CIH, the width on 1.78:1 content would be about 107". To summarize, here's the setup:
Flat Perforated Screen
Screen size (2.4:1 native); 144" x 60"
Screen + masking size: 144" x 81"
Screen position: 10" from drywall ceiling (assuming 6" between drywall ceiling and concrete ceiling), 14" from floor
1.78:1 content size: 107" x 60" (122" diagonal)
(2) CIW w/ top/bottom masking: Native screen AR now is 1.78:1, and the screen can take up the whole area that in the first option is screen+masking. I can use top/bottom masking to hide black bars when viewing 2.4:1 content.
Flat Perforated Screen
Screen size (1.78:1 native): 144" x 81" (165" diagonal)
Screen position: 10" from drywall ceiling, 14" from floor
2.4:1 content size: 144" x 60"
Now, before continuing to option 3, let me say right now that I see no advantages to option (1) over option (2). This statement relies only on the fact that (a) I still need top/bottom masking in the CIH w/zoom setup, and (b) I'm height constrained in my room. Assuming those are true, I see no reason to choose (1) over (2). In particular, I get a *much* bigger image for 1.78:1 content with option (2). Even if you think this screen is too tall, this conclusion should still hold. Also, the fact that it's CIW means I can handle an arbitrary content aspect ratio -- all I have to do is adjust the masks. Further note that because it's zoomed CIH in (1), my projector brightness needs to be exactly the same as in (2).
Now for option 3:
(3) CIH w/ A-Lens. Now, because the top/bottom black bars are truly absent in the 2.35:1 image, I don't need the additional masking that I needed in (1). As a result, I could accommodate a much taller 2.4:1 native screen; in fact, now I become width constrained. After giving adequate space for constructing side walls and framing the screen, I could accommodate a screen that's approximately 14' = 168" wide, and 70" tall. The height of this screen would fit much more comfortably in my room. Here's the setup:
Curved Perforated Screen
Screen size (2.4:1 native): 168" x 70"
Screen position: 10" from drywall ceiling (assuming 6" between drywall ceiling and concrete ceiling), 25" from floor -- note I don't need to fudge the height from the formula here
1.78:1 content size: 125" x 70" (143" diagonal)
So now that you know the choices, here are the pros/cons as I see them -- please add to this list as you see fit:
Option (2) Pros/Cons:
* Much cheaper -- lens itself, flat vs curved screen, bigger screen
* Bigger 1.78:1 content screen
* Screen is too low for all aspect ratios -- about 3" too low for 2.40:1 content, and 7" too low for 1.78:1 content
* Screen is arguably too close to the floor for aesthetic reasons alone
* Bottom of screen may be obscured for middle-row viewers by the front row.
* Easily accommodates any aspect ratio
Option (3) Pros/Cons:
* Much more expensive
* More moving parts (e.g., lens) / clumsier to transition between AR's / more to maintain
* Much bigger 2.4:1 screen (35% by area)
* Much smaller 1.78:1 screen (33% by area)
* Potential image distortions from digital vertical scaling and optical horizontal stretching -- we can debate whether these are visible or not but they are undoubtedly there
* The upside to the above point is the additional pixel gain coming from the digital vertical scaling, assuming the projector does this well
* Screen height should be spot-on
* As I understand it, I'll have to deal with black bars on anything other than 2.4:1 (or, if you prefer, 2.35:1) and 1.78:1
* A much better fit aesthetically
If there are other pros / cons that I'm missing here, I'd greatly appreciate your input, as well as any thoughts you'd have on which option I should choose.
Thanks!
I should say that I'm a relative newbie to these things, so feel free to educate me if I'm getting something horribly wrong here.
I figure that the screen can be no closer than 16" from the concrete ceiling, which gives enough space for building a wood / drywall ceiling, including acoustic and aesthetic treatments, and some space for trim around the screen. I'll need about 3" to build a floating floor. People sitting in the middle-row seats will have their eyes about 48" off the floor. Optimal screen height (based on: Eye Height - Screen Height / 3 = Screen Bottom to Floor distance) puts the screen about 21" off the floor. I could maybe fudge this a little, and move a larger screen 6" lower so it's 15" off the ground.
From what I understand, I have essentially three options:
(1) CIH w/Zoom, left/right masking. Native screen AR is 2.4:1. Now, this is key: I assume that in the zoom setup, I will *still* need top/bottom masking, so small amount of light from the projector's black bars don't bleed onto the surrounding wood cabinet. Consequently I need to in-effect be able to project a full 1.78:1 image onto my screen+masking combo. I am height constrained in my room, to a screen+masking height of about 81". Even that would be pushing it, but this gives me a screen width of 144" = 12 feet. Fits in the width of the room for sure. The image height for 2.35:1 content would be 60". Because it's CIH, the width on 1.78:1 content would be about 107". To summarize, here's the setup:
Flat Perforated Screen
Screen size (2.4:1 native); 144" x 60"
Screen + masking size: 144" x 81"
Screen position: 10" from drywall ceiling (assuming 6" between drywall ceiling and concrete ceiling), 14" from floor
1.78:1 content size: 107" x 60" (122" diagonal)
(2) CIW w/ top/bottom masking: Native screen AR now is 1.78:1, and the screen can take up the whole area that in the first option is screen+masking. I can use top/bottom masking to hide black bars when viewing 2.4:1 content.
Flat Perforated Screen
Screen size (1.78:1 native): 144" x 81" (165" diagonal)
Screen position: 10" from drywall ceiling, 14" from floor
2.4:1 content size: 144" x 60"
Now, before continuing to option 3, let me say right now that I see no advantages to option (1) over option (2). This statement relies only on the fact that (a) I still need top/bottom masking in the CIH w/zoom setup, and (b) I'm height constrained in my room. Assuming those are true, I see no reason to choose (1) over (2). In particular, I get a *much* bigger image for 1.78:1 content with option (2). Even if you think this screen is too tall, this conclusion should still hold. Also, the fact that it's CIW means I can handle an arbitrary content aspect ratio -- all I have to do is adjust the masks. Further note that because it's zoomed CIH in (1), my projector brightness needs to be exactly the same as in (2).
Now for option 3:
(3) CIH w/ A-Lens. Now, because the top/bottom black bars are truly absent in the 2.35:1 image, I don't need the additional masking that I needed in (1). As a result, I could accommodate a much taller 2.4:1 native screen; in fact, now I become width constrained. After giving adequate space for constructing side walls and framing the screen, I could accommodate a screen that's approximately 14' = 168" wide, and 70" tall. The height of this screen would fit much more comfortably in my room. Here's the setup:
Curved Perforated Screen
Screen size (2.4:1 native): 168" x 70"
Screen position: 10" from drywall ceiling (assuming 6" between drywall ceiling and concrete ceiling), 25" from floor -- note I don't need to fudge the height from the formula here
1.78:1 content size: 125" x 70" (143" diagonal)
So now that you know the choices, here are the pros/cons as I see them -- please add to this list as you see fit:
Option (2) Pros/Cons:
* Much cheaper -- lens itself, flat vs curved screen, bigger screen
* Bigger 1.78:1 content screen
* Screen is too low for all aspect ratios -- about 3" too low for 2.40:1 content, and 7" too low for 1.78:1 content
* Screen is arguably too close to the floor for aesthetic reasons alone
* Bottom of screen may be obscured for middle-row viewers by the front row.
* Easily accommodates any aspect ratio
Option (3) Pros/Cons:
* Much more expensive
* More moving parts (e.g., lens) / clumsier to transition between AR's / more to maintain
* Much bigger 2.4:1 screen (35% by area)
* Much smaller 1.78:1 screen (33% by area)
* Potential image distortions from digital vertical scaling and optical horizontal stretching -- we can debate whether these are visible or not but they are undoubtedly there
* The upside to the above point is the additional pixel gain coming from the digital vertical scaling, assuming the projector does this well
* Screen height should be spot-on
* As I understand it, I'll have to deal with black bars on anything other than 2.4:1 (or, if you prefer, 2.35:1) and 1.78:1
* A much better fit aesthetically
If there are other pros / cons that I'm missing here, I'd greatly appreciate your input, as well as any thoughts you'd have on which option I should choose.
Thanks!
