Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!mailrus!wasatch!ug.utah.edu!u-adomma
From: u-adomma%ug.utah.edu@wasatch.UUCP (Alex Dommasch)
Newsgroups: comp.cog-eng
Subject: Re: Color in Screen Displays
Keywords: color, screen display, user interface, fatigue, ergonomics
Message-ID: <794@wasatch.UUCP>
Date: 13 Dec 88 22:23:53 GMT
References: <2789@hound.UUCP> <1724@hp-sdd.HP.COM> <234@lynpac.oz>
Sender: news@wasatch.UUCP
Reply-To: u-adomma%ug.utah.edu.UUCP@wasatch.UUCP (Alex Dommasch)
Organization: University of Utah, Computer Science Dept.
Lines: 22

In article <234@lynpac.oz> croot@lynpac.oz (0000-Admin) writes:
>
>From some work long ago, all I CAN remember is that you should never use
>red-on-blue or vice-versa (eg. red text on blue background). Apparently
>the eye adjusts its focus slightly for some colours, red and blue being
>the worst two (This sounds like crap - and probably is - but the original
>assertion is true), therefore the eye *cannot* focus properly since one of
>the red/blue foreground/background will be slightly out of focus. I know
>that on my terminal, I find it very hard to read. Matt.
>

I recently read an article in Scientific American where they discussed
just this phenomenon.  It turns out that the boundary recognition cells in
the retina (or whereever) only operate on luminance information, not color
information.  So with red on blue, or any other pair of colors with similar
luminances, the eye really sees no boundary at all, and the characters
wander all over the place, or don't form at all.

Alex.

================
Alex Dommasch		u-adomma@ug.utah.edu
Salt Lake City, Utah