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Re: Color Contrast

for

From: Sven Jenzer
Date: Jun 3, 2009 12:20PM

I use the Colour Contrast Analyser made in downunder:
http://www.visionaustralia.org.au/info.aspx?page=628
If you choose the algorithm "luminosity" you'll see wcag 2 applied on
small and big fontsize and you'll understand a little bit more. Wonderful!

Point is a unit for measuring in typograhy:
http://en.wikipedia.org/wiki/Point_(typography) used in DTP.
It is *a fix* measure unit, and used (i suppose!) of WAI for describing
the really good textsize independent of Screen-Resolution.

Pixel, em and % are all relative measures. (Pixel depends on
Scren-Resolution!) And these are the webdesign units, nobody uses points.

kind regards from switzerland
Sven Jenzer
www.access-for-all.h


David Ashleydale schrieb:
> I really love the Color Contrast
> Checker<http://webaim.org/resources/contrastchecker/>;,
> but I have a question about the WCAG 2.0 requirements. It mentions the font
> sizes 18 point and 14 point. If I were to write this requirement in pixels,
> should I use 24 pixels and 19 pixels, respectively? Point size seems to
> depend on screen resolution. For 72 ppi, 14 point and 14 pixels are the same
> size. But at 96 ppi, 14 point is closer to 19 pixels.
>
> Does the WCAG 2.0 checkpoint mean to depend on the screen resolution in this
> way? I'm working with our brand department on a color palette and I need to
> let them know which text/background color combinations provide enough
> contrast, but first they need to know what 18 point and 14 point mean.
>
> Thanks,
> David
>