Performance of various lenses shooting into the sun.

I've been noticing lately when taking some sunset portraits that different lenses are giving me MUCH different results when shooting into the sun.

For example, the 70-200 2.8 II isnt even close to as nice contrast/color wise as the 50L. I have much more trouble focuing with the 70-200 and the images honestly just look pretty bad when you compare them to what I get with the 50L. Shots with the 70-200 look just as good if not better than the 50L when the sun is not in the background.

Has anyone else experienced this or can you give some other examples of lenses that perform well or poorly with a light source in the background?

Some lenses just resist flare better than others. I have to say my Nikon 24-70, 16-35, and 70-200 are annoyingly flare resistant - I like a little flare! I had to buy a cheap lens to get some flare.

35L and the 50L are beasts when it comes to flare. Love using them shooting into the sun.

but my god. the 85L is absolutely useless in that situation, ugliest images.