Thread Subject: Re: Fix to General and REd Flash definition
Note
This archival content is maintained by WebAIM and NCDAE on behalf of TEITAC and the U.S. Access Board . Additional details on the updates to section 508 and section 255 can be found at the Access Board web site.
From: Loretta Guarino Reid
Date: Tue, Sep 04 2007 3:05 PM
- Return to this mailing list's archives
- View all messages in this thread
- Next message in thread: None
- Previous message in thread: Gregg Vanderheiden: "Fix to General and REd Flash definition"
- Messages sorted by: Author | Thread | Date
I'll put this into this week's survey.
Loretta
On 9/4/07, Gregg Vanderheiden < = EMAIL ADDRESS REMOVED = > wrote:
>
>
>
>
> Jared Smith pointed out an oversight in our definition of Flash Thresholds.
>
>
>
> We need to add "when viewed at normal viewing distance" to the end of item
> 3 as shown below.
>
>
>
> I am forwarding this amendment both to WCAG and TEITAC with a recommendation
> to make the change.
>
>
>
>
> general flash and red flash thresholds
>
> a sequence of flashes or rapidly changing image sequences where all three of
> the following occur:
>
> 1. there are more than three flashes within any one-second period; and
>
> 2. the flashing is below 50 Hz; and
>
> 3. the combined area of flashes occurring concurrently and contiguously
> occupies more than a total of .006 steradians (25% of any 10 degree visual
> field on the screen) when viewed at normal viewing distance.
>
>
>
>
>
> Gregg
>
> ------------------------
>
> Gregg C Vanderheiden Ph.D.
> Professor - Depts of Ind. Engr. & BioMed Engr.
> Director - Trace R & D Center
> University of Wisconsin-Madison
> <http://trace.wisc.edu/> FAX 608/262-8848
>
> DSS Player at http://tinyurl.com/dho6b
>
> If Attachement is a mail.dat try http://www.kopf.com.br/winmail/
>
>
>
>
>
>
>
- Next message in Thread: None
- Previous message in Thread: Gregg Vanderheiden: "Fix to General and REd Flash definition"
WebAIM is an initiative of:
