AVS Forum banner
Status
Not open for further replies.
1 - 13 of 13 Posts

·
Registered
Joined
·
130 Posts
Discussion Starter · #1 ·
OK...so I'm VERY seriously considering trying out an X1....but I wanna make sure my numbers are right....


Here are my measurements...


Room: 201" L x 104" W

Screen wall: 104" W x 94" H

Couch: 36" tall (app. eye level), middle of couch is 120" from screen wall


Given those measurements, my calculations give me a decent 80x45 screen at 16:9, and for 4:3 sources I'd go with the 60x45. Viewing from 120" that sounds about perfect.


The screen I'd mount 29" from ceiling, 20" from the floor. This gives me ~15" below eye level.


Given the image offset of 132.9% at 16:9 mode, I'll need to mount the projector upside down, with the center of the lens 14.8" from the ceiling, right?


Does my math sound OK to everyone else? How about my plans of projecting a 4:3 image on the 16:9 screen? Can I do so (using native mode, perhaps?) without having to adjust the pj?



Thanks, guys...I'm new to the whole HT scene, and need all the help I can get...
 

·
Registered
Joined
·
130 Posts
Discussion Starter · #2 ·
also...according to Infocus' Projection Calculator...the "min" screen size for 4:3 at that distance is 80x60...is that correct? Can the projector actually not throw out a 60x45 image at 15 feet? Is my plan of using a 16:9 screen not gonna work?
 

·
Registered
Joined
·
69 Posts
Why are you wanting to limit what the projector is capable of producing? The X1, from what I have gathered in my research as I search for the right projector is a 4:3 projector and therefore you should create the screen for the 4:3 format and downsize if you are using a 16:9 format???


Schwin97
 

·
Registered
Joined
·
130 Posts
Discussion Starter · #6 ·
I think looking at a 80x60 screen from only 10 feet away might be a bit much. Plus, I think maybe a smaller screen would increase image brightness, decrease any pixellation, and possibly decrease likelihood of rainbows...right?


Then again, maybe I'm wrong...just guessing...
 

·
Registered
Joined
·
301 Posts
AnakinOU,


If you want to use a 16:9 screen with the X1 you will lose brightness due to the projector's native 4:3 DLP chip. The extra pixels in 16:9 mode will be turned off, hence less light on the screen. A way around this is to use an anamorphic lens which utilizes all the pixels and also increases brightness in the process of stretching the image into a 16:9 format.


A smaller 16:9 screen will decrease pixellation and potentially reduce rainbows as less light is transmitted than in 4:3 mode.


John;)
 

·
Registered
Joined
·
130 Posts
Discussion Starter · #8 ·
Hmmm...I don't know how to best go about this. I'd use the pj for video games just as much as movies, so whether I'd use 4:9 or 16:9 more frequently is unknown.


If I go with a 4:3 screen, and manually mask out unused portion for movies, and get an anamorphic lens (price? ease of use?)...would the 80x60 4:3 screen be too large for a standard NTSC signal? It seems image quality would be an issues on a screen that large, when viewed from 120".


OTOH, it looks like I can't even go with a 16:9 screen, b/c the X1 won't even project an 4:3 image at less than 80x60 from 15 feet, which gives me a 16:9 screen size of....107x60, which is too large for my wall.


Maybe I'm just comfused.


According to Infocus' calculator, the pj will throw a 80x60 image. If I use it in 16:9 mode, it's giving me a 80x45 image. Will image quality be OK in both modes, when viewed from 10 feet? I'll likely start out with projecting onto a blank wall, whiteboard, or whatever (as a trial to see if image is acceptable), with an upgrade to a good Da-lite HCCV screen shortly thereafter. Does this sound like a good plan?


Again, please forgive any errors or misconceptions...I'm a complete newbie when it comes to projectors...
 

·
Registered
Joined
·
1,975 Posts
The X1 can display a 16:9 image, and in Native mode it will display a 4:3 image inside the size of the 16:9 image (pillar boxed 4:3 within the 16:9 area). I think that is what you are looking for, but it is important that you understand how it does this.


The X1 starts with 800x600 pixels for a full size 4:3. To get 16:9 it "turns off" pixels at the top and bottom to give you 800x450. And in Native mode it can "turn off" more pixels to show 4:3 at 640x450 (or something close to that... can't remember the exact number).


Assuming you don't adjust the zoom as you switch between these three image sizes, then each image is correspondingly smaller because each size uses the same number of pixels per inch. Fewer pixels being diplayed = fewer inches. The unused pixels are kind of masked off (actually, they are just flipped in their least reflective position).


The pixelization/screendoor will remain the same in each mode. The image brightness that you will perceive is ~the same in each mode, because each pixel is getting the same amount of light in each mode. Rainbows (if you see them) will be about the same.. there might be a slight reduction in 4:3 Native mode because your eyes will not have to scan horizontally as far, but in 16:9 the image is the same width as fullsize 4:3.


If you really want a 16:9 screen, the X1 will work fine on it. But if you have room for a 4:3 screen of the same width, then why not go for it. If you decide you need masking for the parts of the screen that aren't being used in 16:9 mode, you would have had the same issues with 2.35:1 movies on your 16:9 screen anyway.
 

·
Registered
Joined
·
130 Posts
Discussion Starter · #10 ·
thanks...that's what I was looking for. That makes sense, but for some reason (wishful thinking?) I thought the 4:3 native mode *might* be refocusing the image within the smaller screen. I'm just really concerned about non-HD 4:3 signals (i.e. older video games and broadcast tv) looking horrible on a 80x60 screen...
 

·
Registered
Joined
·
504 Posts
Forgive me if I am wrong about this, but I am trying to learn as well. The X1 is an 800 x 600 projector in 4:3 format. It will output 800 pixels by 600 pixels. NTSC broadcasts are 640 pixels by 480 pixels. DVDs output 720 pixels by 480 pixels in 16:9 format. If the X1 has to upscale an NTSC signal to 800 x 600, doesn't that result in some signal degredation? If I have a 16:9 screen, and view NTSC in Native format, isn't that 1:1 pixel mapping? The 800 x 600 mode would be perfect for computer resolutions, but if I don't have a need or wish to use the X1 as a monitor wouldn't I be better with a 16:9 screen?


Thanks
 

·
Registered
Joined
·
2,127 Posts
Umm No. When you get the X1, you will see why. 4:3 in big screen mode such as 80x60 has what I call DEEP IMPACT MODE that will floor any guests that come over. The interlacer improves the quality of NTSC to the point of where you won't believe your eyes assuming you have a good signal feed coming in such as cable with an amp attached with few or no splits coming in. Putting 4:3 in a letter box mode within a wide-screen in my humble opinion just doesn't have the same impact and should be avoided....
 
1 - 13 of 13 Posts
Status
Not open for further replies.
Top