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Re: guideline 7.1 about screen flickering (fwd)

From: Anne Pemberton <apembert@erols.com>
Date: Mon, 30 Jul 2001 10:51:20 -0400
Message-Id: <>
To: Marja-Riitta Koivunen <marja@w3.org>, "Jonathan Chetwynd" <j.chetwynd@btinternet.com>, "gregory j. rosmaita" <oedipus@hicom.net>, <w3c-wai-gl@w3.org>

         While your point is well taken, your reason is not based on fact. 
A cognitive system is not built and dropped in place, it is *built* or 
developed over one's lifespan, and not all cognitive systems are built to 
respond the same way to all stimuli whether movement, sound, or images 
(including images of text, since for perhaps most web user, text comes to 
them as an image).

         Most of us trained our cognitive systems before the stimuli under 
discussion was invented. Children growing up with this type of stimuli will 
learn to respond to it more appropriately than us old geezers do.

         Have you tried to read material close to a flickering source? What 
site? so we can all test it. Or do you mean to say that you have tried to 
read material close to a moving source, an animation, for example (like 
that RADAR icon), and you were unable to read the text? How close was the 
animation? Was text size appropriate to the icon or did one overpower the 
other? What site did you test it on? Were there any contributing factors 
preventing your understanding other than the problem graphic? Does this 
happen whenever you encounter certain type of graphics? Is there any reason 
that hitting the stop button (or the equivalent in your browser) is 
insufficient? Does it help to enlarge the text size near a competing graphic?

         An remember, that being irritated or annoyed is not a disability.


At 09:52 AM 7/30/01 -0400, Marja-Riitta Koivunen wrote:
>At 06:49 AM 7/27/2001 +0100, Jonathan Chetwynd wrote:
>>given that placements are a more subtle way of advertising, perhaps in the
>>RADAR case and given the client group, it might make sense to advise that an
>>animated gif is liable to irritate, rather than rely on a medical condition.
>And not only to irritate. Sometimes it makes it almost impossible to read 
>a text that is near a flickering image as our cognitive system is built to 
>pay attention to the movement.
>>jonathan chetwynd
>>IT teacher (LDD)
>>http://www.peepo.com         "The first and still the best picture directory
>>on the web"

Anne Pemberton

Received on Monday, 30 July 2001 10:56:40 UTC

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