Originally Posted by noah katz
A 110" screen is 21% bigger than 100".
I went from a 50" to a 55" daytime TV, and while not dramatic, the difference is appreciable.
im just saying, i went from a 72" tall screen to a 65" tall screen and the difference was negligible.
i remember going from a 46" RPTV to a 50" plasma, and once compensating for foot closer to the wall the screen was, it was a clear difference as well. however, that's the point of the question. before compensating for that difference in viewing distance, i actually felt the 50" looked smaller.
so i stand by it, if you're allowed to move the viewing distance, a 100" vs 110" screen is completely within the range that moving closer can compensate for. i don't however, believe that you could ever find a viewing distance that makes a 50" image feel the same as a 100" image. there's too much change, and you would absolutely pick up on the change in viewing distance.
personally, i would tend to state that screen size is determined by viewing distance, rather than viewing distance is determined by screen size. if you build your room to the dimensions you want/need for the desired seating arrangement, then you'll be left with an idea of how big your screen needs to be. if you start off with your screen size, then there's really nothing to base it off of. is 120" big? 140"? in some cases that's huge, in others tiny. i just don't think it's fair to say that a 120" screen is bigger than a 110" screen (as ridiculous as that sounds, but when it's all said and done, a 110" screen can absolutely feel bigger in a small room than a 120" screen in a big room). so until you have your room size and seating distance, no size screen can be considered 'big' or 'small'
i mean in practice, you're going to go back and forth a bit, you can't always get the ideal screen size, so you might shoot for 2 rows and a 20' viewing distance, then realize you're projector can't fill a 150" screen, and start making adjustments.
ultimately, i don't think our eyes can do a good job of differentiating screen size based on FOV alone, but it's pretty easy to tell the difference in viewing distance(if it's significant). so if the FOV seems the same, but the viewing distance is much shorter, we can easily identify that as a smaller screen. If the FOV is similar, and viewing distance is similar, we might not be able to tell the difference.