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Testing color contrast as a screen reader user

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From: Birkir R. Gunnarsson
Date: Mar 18, 2013 1:25PM

Hey guys

What are the best solutions for detecting color contrast issues on a
webpage as a screen reader user (hence, someone awfully un-sighted)?
If you know the color values, there are various checkers out there
that can be used.
I had some issues using wave.webaim.org on a website. It detected 6
color contrast errors, but my colleague said they were wrong and not
comparing the right things (again, Wave is awesome, so no one take
that as undue criticism, and may be my colleague is wrong, just hard
for me to judge).
If there is a tool that can be used accessibly to color analyze a page
and point out sections that do not comply with WCAG contrast ratio
specs, it'd be awfully neat.
These are very common issues , especially lately, and a lot of
partially sighted folks are complaining to me about it, so if I could
quickly analyze a large number of pages just for that and sort of
start up a campaign to try and make people aware of it, that'd be
neat.

Similarly, keyboard focus outline issues. Do the standard
accessibility tools detect and report on vissible keyboard focus
outlines or not?
I have not seen this with the tools I have tested, so I don't know
whether the focus outline has been just fine on the pages I've tested
with these tools, or whether the tool does not test for that (and may
be it is something that has to be tested manually, though it seems the
focus is defined and styled in the CSS).
Basically I want to work very hard myself to independently do a
non-screen reader specific analysis. There are some things I can't do
well, things that are just purely visual judgements, but I very
strongly want to avoid giving anyone the impression that my
accessibility analysis has to do with whether a page works with a
screen reader, even if it is important.
I have solved this by teaming up with a colleague, who does the visual
stuff, and I do all ARIA and screen reader things, but the more I can
do independently, the quicker I can work and the more pages I can
test, albeit loosely.
Cheers
-B