First, John, thanks for calling my attention to the problem. It turns
out that the biggest problem was using manual focus on the 75-300 mm
lens, because when you set it to what you think is infinity (cranking
the manual control to its stop), it goes "past infinity" and the image
blurs a little. Today's pics are pretty sharp, as you'll see when I
put them up, because I let the autofocus do its thing. It was only
fooled by the B2, which was stealthy to my A100 (lots of focus
hunting, with no finding), but not to the much more expensive Canon
used by the guy next to me. Even then, if I had not set the AF on
spot, I wouldn't have gotten into trouble (imagine what a spot meter
does when that thin sliver of a plane is approaching you!).

I think the purple fringing you saw was an exaggeration of the slight
blur, perhaps exacerbated by other things I did to the images. Anyway,
Paint Shop Pro also has a nice purple fringe killer, which I should
have used, but thanks for mentioning Adobe's since others will have
access to that.

My pics are better because you impelled me to do something about what
I was getting, so thanks man! The pics from today are especially for
you and others who really care about the art.