Thank you everyone for your responses. Yes, chromatic aberration is exactly what it is and I've been able to remove it in post processing. The photos in question were taken almost exactly as suggested in one of the responses...winter tree branches...
Thank you for your response. The white balance is AWB and the pic style is standard. It's not a bluish cast, but a very distinct outline around part of the subject. One of the photos is an eagle landing in the nest...there is a blue line going up ...
