RE: Pop quiz

Full disclosure: I operate with colors inverted always since I am glare sensitive and can’t see much of anything on the screen otherwise.  So the contrast ratio I see is not exactly the same, but very similar.

Looking from a comfortable chair position, C is the only one I can notice quickly.  B takes me several seconds to spot, but then again I learned where to study my gaze from the letters and icon for C.  I can’t see anything next to A without getting very close to the screen.

Glenda’s point is perfectly valid, but random ordering is not a solution.  Again I’ll caution against trying to put together a survey without considering and planning for the many input variables and outcomes to study in an objective, measurable, and statistically significant manner.

The inputs are too many to control in a single study, but all the major ones need to be controlled or recorded (e.g. eye conditions, distance from screen, size of screen, resolution/magnification, focal point of vision, color inversion, other active assistive technology, etc.).

As for outputs, take the pencil I assume?) icon of this email as a single example.  Presenting the same icon at different ratios and asking which I can “see” is very subjective and won’t correlate well to practical usage.  So what other outputs could be studied?  Just off the top of my head:

1.       Varying the screen location and contrast between questions, you could determine if I see it or not in a fixed amount of time (similar to a field of vision test).

2.       Varying the contrast of a typical scenario that icon might be used between questions,  you could ask me to click it with the mouse and time how long it takes me it would matter greatly if other things were clickable, labeled, and what they were though.

The first is more basic research while the second is more about objective usability.  For every type of graphic, the latter becomes very different.  For example, a pie, bar, or line chart is about reading the results correctly in a reasonable amount of time, whereas focus or selection indicator is just about finding it visually in a reasonable time.

I’m happy to help plan a test that I think would be useful, but I do not think a multiple choice contrast survey is going to produce useful results.

Steve

From: Alastair Campbell [mailto:acampbell@nomensa.com]
Sent: Friday, October 20, 2017 11:01 AM
To: Glenda Sims <glenda.sims@deque.com>
Cc: LVTF - low-vision-a11y <public-low-vision-a11y-tf@w3.org>
Subject: Re: Pop quiz

Hi Glenda,

Yep, makes sense, I’m beta-testing at the moment, just need to create more examples first such a survey I think.
Do you know if Survey monkey allows for random ordering?

That’s one side, the “is 3:1 enough” question.

The other side is: “How do you identify and test various graphics”, for which I’ve asked Andrew & Josh for an agenda item at TPAC – a graphics contrast quiz.

I’ll email out to the main list soon asking for examples.

Cheers,

-Alastair


From: Glenda Sims <glenda.sims@deque.com<mailto:glenda.sims@deque.com>>
Date: Friday, 20 October 2017 at 15:53
To: Alastair Campbell <acampbell@nomensa.com<mailto:acampbell@nomensa.com>>
Cc: LVTF - low-vision-a11y <public-low-vision-a11y-tf@w3.org<mailto:public-low-vision-a11y-tf@w3.org>>
Subject: Re: Pop quiz

A is not enough
B is okay  (but this may be due to the surrounding clues giving in C)
C is best

A quiz like this would be cool in survey monkey...where I'm not seeing all 3 at the same time.  Because C is in my field of vision...I can use it to tell me what I should see in B and A.  Once my eyes understand "C"....I think my brain fills in gaps in A and B.

Make sense?
G

glenda sims  |   team a11y lead   |    deque.com<http://deque.com>    |    512.963.3773
web for everyone. web on everything. -  w3 goals

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On Fri, Oct 20, 2017 at 9:42 AM, Alastair Campbell <acampbell@nomensa.com<mailto:acampbell@nomensa.com>> wrote:
Hi everyone,

I’m dealing with github comments and thinking about ratios.

I think most people know the github site to some degree?

Without testing, which of these has ‘enough’ contrast for you?

[cid:image001.png@01D34998.15B64600]

You can probably guess the ratios, so my question is really: Is B enough for you?

The level of difficulty to meet (with various colours) goes up a lot between B & C, does the perceptibility?

To me, there is more difference between A & B than B & C, but I’m not target audience…

Kind regards,

-Alastair

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