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Re: guideline 7.1 about screen flickering (fwd)

From: Anne Pemberton <apembert@erols.com>
Date: Mon, 06 Aug 2001 09:26:56 -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>

         Seems we are very close to agreement here. The concerns you 
mention, such as monitoring the visual presentation of a web page as well 
as the metadata and text tags, needs to be addressed in the techniques for 
the guideline, not in the guideline itself. The guidelines say to separate 
presentation and content, but don't provide advice on what you need when 
you recombine them on a web site, as for a visual presentation, audio 
presentation, etc.

         Yes, you will always find badly designed sites, and some of the 
worst are those that address web accessibility!  And some of the best are 
found from the most surprising sources (see my comments this morning on the 
gold mine on the AFB site for pictures of Helen Keller).  The solution to 
badly designed sites, unless they are educational or government, is to not 
use them .... if they are educational or government, it's worth complaining 
about. The guidelines will never prevent bad design, but if the guidelines 
prevent a badly designed site from claiming to be accessible if it excludes 
too many people by its design. Remember, if the graphic isn't there, no 
matter how badly presented, the user can't choose to use it .... Period ...


At 08:29 AM 8/6/01 -0400, Marja-Riitta Koivunen wrote:
>I very much enjoy graphics and multimedia myself and think it is extremely 
>important. My goal is to make it easy for different users, not disturbing.
>I myself have seen user interfaces that have been designed so that 
>important text is right next to a moving image. This design made it really 
>difficult to concentrate on reading the text as your eyes constantly 
>wondered to the changing image. I don't have examples right now nor time 
>to create them but if you are interested to you can program different 
>variations yourself and see what the effect is. When the image is further 
>away and the movement is less strong the text becomes easier to read.
>Having difficulties in reading text does not prevent enjoying the movement 
>or images especially if the user does not need or care to read the text 
>and does not get epilepsy or other difficulties from the movements. 
>However, if the designer thinks the text is important for users to read, 
>he/she might want to select a different design.
>I think it is important to gather as much knowledge as possible that is 
>related to the guidelines. Another step is then to evaluate the effects on 
>different disabilities and decide how much weight we need to put on 
>different things. For instance, it might be important for users already 
>having difficulties in reading or attention, not to add extra disturbances 
>near an important text or at least let users turn these disturbances off 
>when so wished. That users with good reading abilities or attention also 
>have difficulties does not, in my opinion, make the problem disappear, it 
>is only easier to discover.
>At 07:18 AM 8/1/2001 -0400, Anne Pemberton wrote:
>>         I didn't ask for "good references from the web" that defined 
>> anything, I wanted an example of a movement on an actual site that kept 
>> you, yourself, from understanding what was there. Over the past two 
>> years, I've watched some 650 kids learn to use the computer and 
>> thoroughly enjoyed all the movement included in their games and on the 
>> web sites I gave them to use. So the definition is over-ridden by the 
>> observation of actual people using computer and the web ...
>>A further note: If your intent in this line of reasoning is hope that you 
>>will be able to do away with banner ads on the web, you probably need to 
>>think this through better. Advertisers aren't lining up waiting to hear 
>>our words of wisdom.
>>As for using Jakob Neilsen as a reference is like asking me to read the 
>>wisdom on a sheet of toilet paper. As I told Kynn yesterday, Neilsen has 
>>a disclaimer for not including graphics on his site which is so 
>>overwhelmingly irritating and annoying that I am unable to read anything 
>>else on his site.
>>                                 Anne
>>At 04:00 AM 8/1/01 -0400, Marja-Riitta Koivunen wrote:
>>>I agree we learn to see but many things also develop normally in a 
>>>certain way e.g. in our visual cortex there are cells specialized in 
>>>detecting movement and it is hard keep the eye saccades out of the 
>>>movement if it is strong enough. That is why advertisers want to use 
>>>movement in the banners as it easily get's the user's attention.
>>>I tried to find a good reference from the Web, but it was difficult 
>>>without going too deep and I don't have more time now. The more 
>>>understandable references are similar to this one:
>>>In the visual periphery we can instantly detect even slight movement.
>>>This is an important safety feature, developed long ago to recognize 
>>>stalking predators. The eye's periphery reports a movement, the brain 
>>>thinks it's important, and the vision is automatically centered on the 
>>>threat. It is so imprinted on us that we can't do anything about it, and 
>>>Also Jacob Nielsen refers to it.
>>>At 10:51 AM 7/30/2001 -0400, Anne Pemberton wrote:
>>>>         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.
>>>>                                                         Anne
>>>>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 
>>>>>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.
>>>Anne Pemberton
>>Anne Pemberton
Received on Monday, 6 August 2001 10:13:06 UTC

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