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Re: guideline 7.1 about screen flickering (fwd)

From: Anne Pemberton <apembert@erols.com>
Date: Thu, 09 Aug 2001 14:53:47 -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>
At 12:23 PM 8/9/01 -0400, Marja-Riitta Koivunen wrote:
>At 09:37 AM 8/9/2001 -0400, Anne Pemberton wrote:
>>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 

One does not "easily get epilepsy", although some people with epilepsy are 
subject to more seizure activity than others but for most, seizures are 
controllable with drugs.

Is what you are asking, which poses the greater barrier to the greatest 
number of disabled folks?  I would say that the greater barrier would be 
the absence of the graphic content. If it isn't there, you can't turn it 
on. Plus, how do you expect    those who don't read well, to read the 
directions on how to turn on whatever is on the site? As for those who are 
so distracted by animation that they cannot remember to hit the stop button 
should not be traveling the Internet without binders on .... (i.e. turn off 
graphics or animation in the browser).  After all, you don't tell someone 
to stand in the middle of the street to see if the bus is coming, so when 
you surf the net, you need to maintain your personal safety.

>>         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?

There is no such thing as "going from information towards art" .... they 
are not extremes on a continuum. Art exists in all forms of information. 
And information exists in all forms of art (even the ones you don't 
like).  The guidelines cannot and should not try to say which or what 
should be there, just that the content be as varied as possible to aide 
comprehension. One page author may do that with a still picture, another 
with an animation, and other with a multi-media presentation, all with 
various amounts of text content. The only thing the guidelines should 
address is that the presentation should never be in a single modality, such 
as text, if it's going to be used by the greatest variety of people.

>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?

Minimum is one image per page, preferably a topical illustration or logo. 
Every image more enhances the graphical usefulness of a page. Too many 
doesn't exist. You can have a page or site with 200 images on it, and there 
would be no way to determine if that is "too much" .... (unless they are 
200 images of the exact same picture, but then there is probably a reason 
to do that if someone does).  Many an unclear message has been made clearer 
by illustrating what you mean. Ever notice how often people draw on napkins 
(etc.) when deep in discussion?

>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 really think you are putting the shoe on the wrong foot on this issue. 
There are billions of people who are aided by graphics, and not a single 
occurrence of an epileptic seizure caused by anything on the web ... 
perhaps, I should qualify that with a yet .... so there is no reason for 
epilepsy to be a concern to a web author. The problems with distractability 
are squarely in the user's court. If you're distractability is so bad you 
can't use the stop button, then travel with graphics off until you see what 
is on a site and feel safe turning them on. If the animation distracts you 
from reading, you can either turn it off, or enlarge the text size.

>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, I have probably repeated myself on this list far too many times 
already, but the whole issue boils down to this. If graphics are there, 
folks can choose to use them or not. If they are absent, the user has no 
choice, and if text isn't useful, the page is inaccessible. You will bar 
many people from your all-text site, but you will bar none from a site that 
is all-graphics (as long as it has alt tags and long descriptions as 
needed). A site with both text and graphics is the ideal solution for the 
greatest number of disabled people, and regular folks as well.  An 
accessible  site has both. The guidelines need to say that much ... the 
rest is up to the web authors....


>>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)
>>>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.
>>>At 09:26 AM 8/6/2001 -0400, Anne Pemberton wrote:
>>>>         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.
>>>>>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 shouldn't.
>>>>>>>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
>>>>>Anne Pemberton
>>>>Anne Pemberton
Received on Thursday, 9 August 2001 15:00:17 UTC

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