Originally Posted by Olrocker 
These were at 2.0 or 2.8, I think.
If I can quote Klaus Schroiff... "
Typical for many ultra-large aperture lenses you can experience some purple fringing in extreme contrast conditions at wide-open aperture."
It isn't pretty and can be a P.I.T.A. to correct, but it's completely normal behaviour when shooting wide-ope or nearly wide-open on a lens like this. Unfortunately few lenses are perfect
