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Re: Color Contrast Formula

for

From: reply-to:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:references;
Date: Mar 16, 2005 3:10AM

On Wed, 16 Mar 2005 09:54:53 -0000, mark.magennis wrote:
>
> > For example, I am using rgb(153,255,51) for a font color on a
> > background of rgb(204,102,204)....
> >
> > If I change the font color to rgb(102,204,0), I get a color
> > difference value of 510
>
> By my calculation, the difference value is 408.
>
> max(red1,red2)-min(red1,red2) = 204 - 102 = 102
> max(grn1,grn2)-min(grn1,grn2) = 204 - 102 = 102
> max(blu1,blu2)-min(blu1,blu2) = 204 - 0 = 204
>
> Am I missing something?

There are two very useful tools available that can help with checking
colour contrast.

Online - http://www.juicystudio.com/services/colourcontrast.asp
Offline - http://www.nils.org.au/ais/web/resources/contrast_analyser/index.html

Cheers,

pix
http://www.pixeldiva.co.uk