First post here - I thought I'd give it a try because I've posted this on Apple's forums as well as Digital Photography section on MacRumors.com (has been my "regular" forum for years) and have yet to get any replies at all after hundreds of views
I've read some extensive
threads here on Luminous Landscape and was really impressed by the depth and quality of discussions here, so hopefully I can finally get this question answered!
In Aperture (version 3.2.1, though it's been happening for well over a year and I just never got around to asking), I noticed something perplexing about it's white/black clipping overlays (View > "Highlight Hot & Cold Areas").
I will say right away that my Preferences for "Hot Area threshold" and "Cold Area threshold" are at 100% and 0%, respectively - so that's not the problem.
(so at this setting, Aperture should only be highlighting clipping if RGB & Luminance levels are 0 or 255)
Since screenshots taken in OS X don't show the mouse cursor, I've uploaded a sample RAW file if you want to follow along as I'm describing it...http://cl.ly/BoUD
The Aperture puts the white balance initially at 5487k and at this setting, the clipping overlays show "properly" - only pixels of 255 RBG/L values are highlighted as clipping.
However, I notice when I make a white balance adjustment, this doesn't seem to be the case, despite the setting in Preferences.
I'll use a more extreme example to illustrate my point...let's change the white balance color temp to 9000k. At this point, you should see a clipping overlay over the person's nose. However, if you mouse over the overlay on his nose, there are plenty if pixels that have not reached a 255 value that are highlighted as "clipping" (ie. R249 G224 B180 L226).
Why is this?