Hi Jim,
Interesting comparison there.The stars a much tighter in the Nikon yet on the very bright stars there is still some CA. Was the Nikon lense at 70mm and what F ratio is it. I find with the old takamar lenses if you stop them down a few stops it makes a lot of difference. I had a look at a pic of the same area I have taken with a old 50mm f/1.4 stopped down to f/3.5 and the stars would be as tight and as well corrected as the ED lense. My other pentax lenses are much the same except when you get to the longer focal lenghts they start to fall behind.....I would like to see the comparison with your pentax stopped down and compared again..
Cheers Gary....
