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Re: Questions about Evaluating Web Sites...

From: Chuck Letourneau <cpl@starlingweb.com>
Date: Fri, 24 May 2002 08:24:05 -0400
Message-Id: <>
To: Charles McCathieNevile <charles@w3.org>
Cc: <w3c-wai-eo@w3.org>
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. On
>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.

Received on Friday, 24 May 2002 08:40:43 UTC

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