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From: jfarrell@sun.UUCP (Jerry Farrell)
Newsgroups: net.cog-eng
Subject: Re: Super 80x24 Display Screen Design
Message-ID: <298@sun.UUCP>
Date: Mon, 22-Aug-83 14:43:04 EDT
Article-I.D.: sun.298
Posted: Mon Aug 22 14:43:04 1983
Date-Received: Mon, 22-Aug-83 22:57:33 EDT
References: cbosgd.210
Lines: 23

re viewing distance:  I know of at least two factors:

1)  The muscles that focus the lens of the eye relax to infinity;  the closer
    your reading matter is, the harder they have to squeeze down;

2)  ditto the muscles that converge your eyes;  these alos have to span wider
    subtended angles if the same absolute-length line of text is closer.
    (read "also" for "alos" 2 lines above")

Obviously, if poor fonts / focus / resolution make the screen illegible at
an "optimal" distance, then it will be more comfortable to work closer.
Font size is a tradeoff between quantity (& therefore context) and legibility
if you're lucky, (Perq, Sun, Symbolics, Xerox, ....) you get to choose the
tradeoff yourself.


re most comfortable colors:  I would appreciate it if people singing the praises
of changeable colors would note whether they are working with a more-or-less
standard monitor.  My recollection from about 5 years ago is that writing a
lower-case 10-point 'o' to the corner of the screen left 3 disjoint circles,
one red, one green, one blue, on an Ikegami converged to spec.  In such a
situation, the legibility vs quantity tradeoff above applies;  how big are
your fonts, folks?