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Re: guideline 7.1 about screen flickering (fwd)

From: Marja-Riitta Koivunen <marja@w3.org>
Date: Thu, 09 Aug 2001 12:23:33 -0400
Message-Id: <4.2.2.20010809102711.024e6270@localhost>
To: Anne Pemberton <apembert@erols.com>, "Jonathan Chetwynd" <j.chetwynd@btinternet.com>, "gregory j. rosmaita" <oedipus@hicom.net>, <w3c-wai-gl@w3.org>
At 09:37 AM 8/9/2001 -0400, Anne Pemberton wrote:
>Marja,
>
>         Nice site! It is good study in the science of perception ... I 
> tried covering the animation while reading and it did not make the 
> reading easier, but more difficult since my eyes couldn't shift to the 
> illustration at the necessary time when reading about the various 
> effects, perceptions, and how to make it ...

Like I said it is not the best example of the phenomenon.

>On a site like this, is would not be useful to have the animation stop 
>after one or two times .... Hard to read fast enough to know what you're 
>looking for before it stops and you have to it the back button to 
>re-animate it ... what a hassle!

I was happy myself for being able to stop the images when I wanted to, but 
what about people who easily get epilepsy or who have difficulties with 
attention? They would probably be happy not having to find a  stop button 
or a way to stop the movement while all the moving is happening around them 
and making it more difficult. So which one is a bigger accessibility problem?


>         The determination of whether or not an animation should be 
> included on a page cannot be constrained to what is "necessary". Opinions 
> on what constitutes "necessary" will vary. Is it "necessary" to have an 
> animation of Santa and his Sleigh on a Christmas page for children or 
> families? If not deemed "necessary", is it the role of the Guidelines to 
> say you can't add it?

I agree, in general it is hard to define what is necessary as it varies. 
And when we go from informational material towards art it becomes even less 
clear. If you think it is impossible to say weather having an animated 
Santa is necessary, wouldn't it be also hard for the guidelines to say it 
should be there?

If this is true, how could we still encourage designers to add images that 
help users to understand the message? When do we have enough images and 
when too many? If the message is unclear from the beginning how can the 
images make it clear? How much learning should we expect the users do to 
understand the meanings of the images? And how to encourage them to be 
sensible to users having problems with movements that cause epilepsy or 
make it harder to concentrate on reading?

I use and want to use images and visual design and I do understand the 
benefits when they are used skillfully.  However, I also see the problems 
when trying to control it too much with conforming guidelines. For me, it 
is more straightforward to try to avoid strong movements at certain 
frequencies when they are not absolutely necessary to convey my message, 
and let the user choose whether or not and when to run them if I think they 
are needed than try to communicate the text with images and know when I 
have done enough. I wonder if it is possible to find less general 
requirements also for the use of images e.g. the main categories of 
information on a page should be visually distinguishable without reading 
the text or whatever is the main requirement for these users (maybe you 
already did that).

Marja


>                                         Anne
>
>
>
>At 06:29 PM 8/7/01 -0400, Marja-Riitta Koivunen wrote:
>>I found one site with some Quicktime motion examples (if you worry about 
>>flickering don't try it)
>>
>>http://www.biols.susx.ac.uk/home/George_Mather/Motion/index.html
>>
>>The site is more explaining the effects than trying to demonstrate 
>>difficulties in reading text so there are still better examples. But try 
>>to make sense of the text explaining the phenomenon when the images are 
>>moving and then stop them or cover them and see if the reading becomes easier.
>>
>>I don't have a suggestion for the actual guideline text right now. This 
>>is partly handled at UAAG by letting the users turn movement off and 
>>giving control of the frequency or selected steps.
>>
>>Sometimes the use of these kinds of images is clearly necessary, as in 
>>the example site, but here the user could initiate them as in my opinion 
>>the movement is not needed for directing user's attention. The images are 
>>pretty visible anyway. The animation could also automatically stop after 
>>the first couple of rounds if it is not initiated by the user. In 
>>addition, as you said, they could be labeled with some metadata so that 
>>they could be filtered etc.
>>
>>Marja
>>
>>At 09:26 AM 8/6/2001 -0400, Anne Pemberton wrote:
>>>Marja,
>>>
>>>         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 ...
>>>
>>>                                                 Anne
>>>
>>>
>>>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.
>>>>
>>>>Marja
>>>>
>>>>At 07:18 AM 8/1/2001 -0400, Anne Pemberton wrote:
>>>>>Marja,
>>>>>         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 shouldn't.
>>>>>>
>>>>>>
>>>>>>Also Jacob Nielsen refers to it.
>>>>>>http://www.useit.com/alertbox/9512.html
>>>>>>
>>>>>>Marja
>>>>>>
>>>>>>At 10:51 AM 7/30/2001 -0400, Anne Pemberton wrote:
>>>>>>>Marja,
>>>>>>>
>>>>>>>         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 
>>>>>>>>>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.
>>>>>>>>
>>>>>>>>Marja
>>>>>>
>>>>>>Anne Pemberton
>>>>>>apembert@erols.com
>>>>>>
>>>>>>http://www.erols.com/stevepem
>>>>>>http://www.geocities.com/apembert45
>>>>>
>>>>>Anne Pemberton
>>>>>apembert@erols.com
>>>>>
>>>>>http://www.erols.com/stevepem
>>>>>http://www.geocities.com/apembert45
>>>>
>>>>Anne Pemberton
>>>>apembert@erols.com
>>>>
>>>>http://www.erols.com/stevepem
>>>>http://www.geocities.com/apembert45
Received on Thursday, 9 August 2001 12:26:48 GMT

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