Path: utzoo!attcan!uunet!snorkelwacker!mit-eddie!bu.edu!xylogics!world!katefans
From: katefans@world.std.com (Chris'n'Vickie of Kansas City)
Newsgroups: comp.graphics
Subject: Re: HDTV
Message-ID: <1990Mar1.093852.167@world.std.com>
Date: 1 Mar 90 09:38:52 GMT
Distribution: comp
Organization: The World
Lines: 35


<1990Feb26.215623.9194@imax.com> dave@imax.com (Dave Martindale) writes:
>> [...]
>> NTSC television is intended to be viewed from a distance of about 10
>> times the picture height. [...]

 <2240@alfred.Teknowledge.COM>tbarnes@teknowledge.com (Terry A Barnes)
> Is this true - I've read articles with varying ideal measures of how
> far the eye should be from the screen - 5 times the diagonal, 8 times
> the height (which is almost the same thing), 6 times the diagonal, etc.
> Does anyone have a definitive answer?
>
> What are the effects of closer viewing - eye strain, visible scan lines,
> what? I'm tempted to get a 30+ inch monitor when I upgrade, but what if
> the couch is only 10 feet from the screen - would I be sorry I got a
> "too big" screen?

  I don't have a definitive answer but I do have considerable personal
experience with big TV's, as I live with a 6' x 8' Sony projector that I
view from a distance of 12'. The vertical scan lines can be visible but
are relatively unimportant compared to convergence, focus, linear response
and chroma crawl. My opinion is that most of the eye strain and stress
associated with normal TV viewing is due to the fact that you are looking
directly at a light source. Projectors cast light on a screen and are no
more stress causing than any film image on the same screen.  Projectors
can be sharper than any normal crt because of the lack of a shadow mask
and the resulting RGB "triplets", purity problems and horizontal resolution
limits. I find the 12" monitors on my graphics system to be more stressful
in spite of the far higher resolution (and not just because they are at
work :-)) In short, I don't believe that a TV can be "too big" and I want
Hi-Definition very badly. These "experts" must be people who sit in the
back row of theaters.

                                  Chris Williams
                                  katefans@world.std.com