I have a photo that I've edited in aperture. I need to change the dimensions from 3x4 to square for posting on FB. When I select 'edit with adobe photoshop cs5' the image processes for a few moments while cs5 opens. when the image appears, everything that was white has a strong pink coloration. what was once a white background is a strongly pink as pink can be. how do I lose the pink?
This is likely a color profile mismatch. What do you have at "Aperture➞Preferences➞Export➞External Editor Color Space"? Try setting it to "No Profile Selected".
If you do select a profile, make sure it matches whatever you are using in PS.