WTF??? |
I gave up and went to sleep only to be reminded of my problem when I looked at the file the next morning. I looked at the Layers dialog and systematically turned off visibility for every layer and even with everything off, there was still this red--now coloring the transparent image canvas.
Without QuickMask |
A mouseover tool tip told me that this was enabling "Quick Mask" and when I clicked it, my red hue was gone. Halle-freakin'-lujah!
So what's this Quick Mask thing and why do I care?
Apparently, Quick Mask allows you to select parts of your image that you wish to protect, then turn on Quick Mask to select everything else and apply filters, edge effects, etc. The tutorial on it is here: http://www.gimp.org/tutorials/Quickmask/
Looks slick, but if you don't know what it is and you accidentally turn it on, it's a pain in the a$$.