Denis BoudreauDeque Systems, Inc.

db@deque.com@dboudreau

Why Browser Zoom

For Low Vision UsersSUCKS

An <a11yRant/> production.

Wayne DickCSU Long Beachwaynedick@knowbility.org

It all started with this.

Or rather, this… (200%)

Actually, maybe even this… (300%)

But more specifically, THIS.

No, not

THAT KIND

of agnosticism,

but rather…

Thomas Henry Huxley (1869)

Leading to heated internal debates

Browser Zoom!Text Resize!

Why BOTHER

with SC 1.4.4 if it

NEVER FAILS!

Web Developers vs. End Users

Web Developers vs. End Users

What Web Developers Want

Easy SolutionsReliable TestingMeasurable

Results

Browser Zoom

Web Developers vs. End Users

What Web Developers Want

Easy SolutionsReliable TestingMeasurable

Results

Browser Zoom

VS.What Low VisionUsers Expect

Robust SolutionsAdaptive InterfacesUsable Content

Text Resize

WHO estimates 285 million visually impaired people worldwide.39 million are blind. 246 have low vision (7.3x as many).

As opposed to the United States population…

Or even Canada’s!

Our job is not to go easy on developers who should know better, but to help foster digital equality for everyone.

Browser Zoom Only Testing

IS POINTLESS

for HTML Accessibility

Browser Zoom Only Testing

IS POINTLESS

for HTML Accessibility

»»» So what about the end users???

Web Developers vs. End Users

Visual Concepts

Acuity LimitCritical Print Size (CPS)Feasible Print RangeCost + Technology +Reader Preference => CPSTo read you need CPS + Word Wrapping

Image of graph of reading speed (vertical) by font size (horizontal)… very simplified.

Is Zoom bad for Everything?

NO!Zoom is great for spot work near the acuity limitSmall Control forms can be zoomed and operatedZoom just fails for reading.The reason follows

Why?

Enlarged content presented for users with full sight is not the same as content presented for users with compromised sight.

Specifically

Lack of word wrapping creates semantic discontinuity

Discontinuity creates data loss and noise Now let’s quantify the data loss and noise

Figure1:A Simple Text Standard Print

Figure 2:Same Text Zoomed with NO Reflow

Same Text Enlarged WITH Reflow

Counting Words

Figure 1: 113 words

Figure 2: 36 words (counting partial words)

Figure 3: 35 words

At a glance, Figure 2 looks as efficient as

Figure 3

Continuity

• Figure 1 (standard print) and Figure 3 (large

print wrapped) present contiguous data.

• In of the language in the essay the first word of

each line is the immediate successor of the last

word on the preceding line.

• This is true for Figure 1 and Figure 3 even

though Figure 1 has 3 times the words.

• Even though Figure 3 reduces the quantity of

data every word on the page is useful.

Discontinuity and Noise

• Lines are not connected in Figure 2 (Zoom NO Wrap).

• Consider the highlighted line, “Screen magnifier

users may.”

• The last visible preceding word is truncated “assisti”

• Between “assisti” and “Screen” are four words and

“ve”, the tail of “assistive”.

• This means on line has any real meaning.

• The rest are noise

Data Loss

• In the first and third figure there is no noise.

• In Figure 2 (NO Wrap). – Looking at the highlighted line (the signal) we have 4 words

– The remainder the disjoint lines, words we have 32 words

– Thus only 1 in for words on this view port have meaning as

we read the highlighted line.

• Figure 3 has 35 words, Figure 2 has 36 but

• Every word on the Figure 3 (WITH Wrap) viewport is

useful

• Only 1/8 are useful in Figure 2 (NO Wrap)

The Burning Question?

• Is zoom without reflow a functional

tool for reading?

• Is screen magnification reasonable

accommodation?

• Does screen magnification constitute

accessibility support for WCAG 2.0

criteria?

Open Discussion

Thinking RWD

Web Developers vs. End Users

Bake SC 1.4.4 straight into your CSS

Thank you!

Photo Creditshttp://gigaom2.files.wordpress.com/2012/08/shutterstock_97220924.jpg http://udemand.files.wordpress.com/2012/07/14.jpg http://taoofman.com/wp-content/uploads/2012/06/ToM_EnsoCircle.png http://www.information.dk/sites/information.dk/files/media/2009/05/01/20090501-174730-pic-363902257.jpg http://www.namespedia.com/image/Huxley_2.jpg http://www.flickr.com/photos/xurble/196294004/ http://free-illustrations-ls01.gatag.net/images/lgi01a201309211700.jpg http://www.flickr.com/photos/kingdesignchile/9023900039/ http://ministry127.com/sites/default/files/Avoiding%20the%20Traps%20of%20the%20Teen%20Years-blank.jpg http://www.sciculture.ac.uk/files/2013/12/Ignite-Event-Image-2.jpg http://www.abortionmemorial.com/wp-content/uploads/2013/07/blurred-vision.jpg