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Re: Color contrast (Minimum)

From: Elizabeth Pyatt <ejp10@psu.edu>
Date: Tue, 16 Aug 2016 16:01:39 -0400
Cc: IG - WAI Interest Group List list <w3c-wai-ig@w3.org>
Message-Id: <F8689AEC-52D8-4CC2-A7F2-EA4446CA4DA4@psu.edu>
To: "Ta, Duc" <duc.ta.740@my.csun.edu>
From Photoshop, the colors I extracted were

#000000 (Black)
#cc0000 (red)

The contrast is 3:6:1, so is technically a pass for large text at level AA…but I don’t like it either.

In Photoshop, I then used the Hue/Saturation filter to make a grayscale version and the red became gray #666666, which is 3.7:1 and also passes for large text.  See attached below:



I would say that people need to watch which filters they use. But also skirting the bare minimum isn’t always working.

My two cents.
Elizabeth

P.S. On a side note - red/black should be avoided in any case because some color blind users see red as black…so you would have black/black text for this group.



> On Aug 16, 2016, at 3:42 PM, Ta, Duc <duc.ta.740@my.csun.edu> wrote:
> 
> Here is the picture of 
> 
> <image.png>
> 
> 
> But when applied black and white (greyscale) effect:
> 
> <image.png>
> 
> 
> 
> Sorry for any confusion here. 
> 
> 
> 
> On Tue, Aug 16, 2016 at 3:40 PM, Ta, Duc <duc.ta.740@my.csun.edu> wrote:
> The color code for it is #CC0000 which clear indicates the contrast ratio is 3.6 : 1. My question is if a person only see black and white which is the applied effect then does the text considered to be a failure or we can say it pass. Or may be I overthink the issue here. 
> 
> 
> Regards,
> Duc Ta
> 
> On Tue, Aug 16, 2016 at 3:20 PM, Elizabeth Pyatt <ejp10@psu.edu> wrote:
> So what were the original color values for the reds?
> 
> I’m trying to understand how the contrast algorithm is effected when the example becomes black and white.
> If it’s a luminosity scale (i.e. values only are measured), then theoretically shifting or removing the hue should not matter. If it does, there is an issue that needs to be investigated.
> 
> Hope this makes sense.
> 
> Best
> Elizabeth
> 
> 
> > On Aug 16, 2016, at 3:06 PM, Andrew Kirkpatrick <akirkpat@adobe.com> wrote:
> >
> > From: "Ta, Duc" <duc.ta.740@my.csun.edu>
> > Date: Tuesday, August 16, 2016 at 13:53
> > To: Andrew Kirkpatrick <akirkpat@adobe.com>
> > Cc: WAI-IG <w3c-wai-ig@w3.org>
> > Subject: Re: Color contrast (Minimum)
> >
> > The actual color is dark red background and the text is red. However, when I check black and white mode, it turns out to be that so i am not sure whether I should consider it as a failure or I will say it is decent and move on.
> >
> >
> > Best,
> > Duc Ta
> 
> =-=-=-=-=-=-=-=-=-=-=-=-=
> Elizabeth J. Pyatt, Ph.D.
> Instructional Designer
> Teaching and Learning with Technology
> Penn State University
> ejp10@psu.edu, (814) 865-0805 or (814) 865-2030 (Main Office)
> 
> 3A Shields Building
> University Park, PA 16802
> http://www.personal.psu.edu/ejp10/psu
> http://tlt.psu.edu
> 
> 
> 
> 
> -- 
> --------------------------------
> Duc Ta
> IT Consultant
> Tel:   (323) 412-4894
> www.dtaconsulting.org
> 
> 
> 
> -- 
> --------------------------------
> Duc Ta
> IT Consultant
> Tel:   (323) 412-4894
> www.dtaconsulting.org

=-=-=-=-=-=-=-=-=-=-=-=-=
Elizabeth J. Pyatt, Ph.D.
Instructional Designer
Teaching and Learning with Technology
Penn State University
ejp10@psu.edu, (814) 865-0805 or (814) 865-2030 (Main Office)

3A Shields Building
University Park, PA 16802
http://www.personal.psu.edu/ejp10/psu
http://tlt.psu.edu
Received on Tuesday, 16 August 2016 20:02:04 UTC

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