Lens review
2007-09-21
Sigma 50-150mm f/2.8 APO EX DC HSM
8. Vignetting
We did not expect Sigma 50-150 mm to perform better than 70-200 f/2.8 model on our APS-C dSLR in this category. And we were actually right.
For 50 mm at f/2.8 light falloff in the corners is 24% (-0.79 f-stops). If we stop down aperture to f/4, light falloff is only 10% and at f/5.6 it is almost gone (3%).
Performance at 100 mm is very similar. At wide-open aperture light falloff in the corners is 26% (-0.88 f-stops). For f/4.0 it is 12%, and for f/5.6 only 5%.
Worst situation is at 150 mm. Here at f/2.8 vignetting is equal to 33% (-1.16 f-stops). At f/4 it is still noticeable and equal to 18%. Only at f/5.6 it is reduced to 11% and at f/8 it disappears almost completely (5%).
