Lens review
2007-09-27
Sigma 100-300 mm f/4 DG EX APO IF HSM
7. Coma and astigmatism
There is no such thing as coma for Sigma's 100-300 mm designers. The coma is corrected perfectly, which can easily be noticed in the picture below.

The astigmatism is also almost entirely absent. For the Sigma it measures 4.5%, which is completely invisible at 100 mm focal length and just a little bit bigger at 200-300 mm.



