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Re: 508 Refresh and Reasonable Accommodation for Low Vision

From: Mike Elledge <melledge@yahoo.com>
Date: Wed, 18 Feb 2015 22:40:50 -0500
Cc: WAI Interest Group <w3c-wai-ig@w3.org>
Message-Id: <686E2065-023E-45CB-AF67-F76F6B5A0F17@yahoo.com>
To: Wayne Dick <wayneedick@gmail.com>
Not to put too fine a point on it, but horizontal scrolling is a usability issue to me; something to be avoided for everyone's benefit. 

I can imagine, however, that it may not occur to everyone, so maybe an SC or related F would be helpful. 

Mike



> On Feb 17, 2015, at 8:33 PM, Wayne Dick <wayneedick@gmail.com> wrote:
> 
> There are a few key point to not in my article:
> 
> First there is a double standard regarding word wrapping. Neilson, Normal and almost everyone who study human factors agree that horizontal practice is a worst practice in web authoring.  There have been extensive studies and their results are consistent.  Users find a need to horizontal scroll one of the most disruptive activities possible.  Of curse we are speaking of left to right languages. Legge and many others have studied horizontal scrolling and its effect on reading.  People read slower and they cannot find items well.  I will not give my references here.  When I testify in San Diego I will give a complete bibliography.  My graduate students will be working to help me compile this material.  There is no evidence that shows horizontal scrolling improves reading speed or comprehension.
> 
> Now let us be precise.  Most people with low vision read in a range of 20-48 point font.  A point is measured using the Adobe metric 1/72". One of the problems with 1.4.4 and 1.4.3 is that they do not specify 200% of what size. That is just too sloppy to be therapeutic.   Many people who read visually use up to 60 point, that is 5/6".  Now these sizes are not useful on cell phones or small tablets.  Although, I use 24 point on my Dell Venue 8, and I can read holding it up close.  However, it is a serious struggle. My laptop is the real device I carry on the bus. Remember, most of spend lots of time on the bus so it is really important to have a portable reading device.  A rule of thumb is, a laptop is our tablet and a desktop is like a laptop.
> 
> However, people who need enlargement usually choose 13" screens and up.  Now, most screens these days are really close to 30/60/90 triangles if you look at the triangle subtended by the diagonal.  So to compute point size is easy.  If the diagonal is 13" and the resolution is 1600/900, the number of pixels per point is p=(900/((1/2)*13))/72.  So 48 pt = p*48px. In our case that is 48pt = 92px.  Since our page is 900 pixels high, we can fit about six lines on a page with 1.5 spacing.  Width is a little narrower than height in general, but lets just say it is 92px again.  The width is 1600 px.  So we can fit in about 17 characters or 3 words.  That means we can get 6*3=18 words on a page.  That is a good chunk and well worth arranging that way.  With 60 point that number goes down, but the arrangement is still significantly better than a zoomed image. At 36 point we get more like 8 lines and 4 words per line.  A 32 word page is very readable.
> 
> Now the real show stopper is the loss of 1194.22(d): d) Documents shall be organized so they are readable without requiring an associated style sheet.  WCAG 2.0 killed this and provided no replacement.  Early in the process I thought 1.3.1 was the replacement, but WCAG WG is very clear that flexible data does not include visual flexibility.
> 
> This paragraph protected us.  We could always restyle a page.  Word wrapping was never a problem with a site that met 1194.22(d).  Just strip the style and restyle or just enlarge.  Either way word wrapping was not a problem.  Without this protection, the 508 Refresh is empty for low vision.
> 
> So, if 508 rally omits the ability to strip author style and provide reasonable restructuring, then I will do everything I can to slow it down.  508 cannot erase the gains low vision made in reading as a result of the current 508.  My group the Council of Citizens with Low Vision, an affiliate of the ACB will not stand for it.
> 
> Sincerely Wayne Dick
> 
> 
> 
> 
> 
> I have used all of these sizes depending on my task at hand and my level of fatigue.  Oh, did I mention, horizontal scrolling is really fatiguing. It requires a greater cognitive load that continuous reading with word wrapping.  Once again there is a mountain of data available on this finding.
> 
> 
Received on Thursday, 19 February 2015 03:41:20 UTC

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