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Re: Accessible color and contrast for projected presentations

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From: Tim Harshbarger
Date: Sep 2, 2014 6:29AM

Sean,

I'm not sure that applying the same contrast ratio to slides being displayed during a presentation at a conference would work.

I took a quick look at the associated success criteria because I thought I recalled something in the calculation that might impact how well it would work for this situation:
http://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html

I believe part of the formula needs to take in account the ambient lighting and the calcuation assumes an average which might not be appropriate for such a setting. But based on the various degrees of lighting that I've experienced in the past in conference rooms, the amount of lighting could alter the calcuation. I don't know how significantly it might alter those values though. It might be inconsequential or significant.but I suppose you could try to take a guesss at common lighting scenarios for conference venues.

Thanks,
Tim