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RE: Questions about Evaluating Web Sites...

From: Audrey J. Gorman <agorman@megsinet.net>
Date: Tue, 28 May 2002 12:43:02 -0500
Message-ID: <01C2064E.1A650900.agorman@megsinet.net>
To: "'Chuck Letourneau'" <cpl@starlingweb.com>, Charles McCathieNevile <charles@w3.org>
Cc: "w3c-wai-eo@w3.org" <w3c-wai-eo@w3.org>
I can't point to anything either. I do agree that for checking contrast 
gray scale is superior to black & white. That leads me to think that we 
should lean to checking gray scale, since we have no control of the 
algorithms in two-color.

-----Original Message-----
From:	Chuck Letourneau [SMTP:cpl@starlingweb.com]
Sent:	Friday, May 24, 2002 7:24 AM
To:	Charles McCathieNevile
Cc:	w3c-wai-eo@w3.org
Subject:	Re: Questions about Evaluating Web Sites...

Regarding my question of black-and-white versus gray scale testing for
contrast problems, Charles wrote:

>Well, 2 color is about the extreme limit of conditions that people have. 
>the other hand, there are people who need that kind of setup, so I would
>think it is a reasonable thing to do.

I think my concern with two-color viewing or printing is that the algorithm 
that decides whether to replace a color with black or with white may lead
to unrealistic contrast displays.  It would seem likely that some color
combinations that would appear very similar in a good gray scale rendering
(and thus be shown to have too low contrast) could be rendered very clearly 
if black and white were the only choices the system had.

Maybe this is too unlikely a scenario. Unfortunately, I  don't have an
example I can point at to support my concern - just a memory of having
encountered the problem at some time in the past six years.  I don't think
we need to pursue this further unless the working group has strong feelings 
about changing the point.

Chuck << File: ATT00000.htm >> 
Received on Tuesday, 28 May 2002 14:46:51 UTC

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