Comparison of 50mm lenses

The following comparison demonstrates the differences between several prime and zoom lenses at 50mm (equivalent to 75mm on cameras with crop factor 1.5x)

Minolta 50/1.7 RS
Sigma 50/2.8 Macro
Tamron 17-50/2.8
Sigma 28-105/2.8-4.0
Minolta 35-105/3.5-4.5

The camera used in the test was a Minolta 7D DSLR, mounted on a tripod and with Anti-Shake disabled.

Below is a downsized version of the test shot. The red rectangles mark the crop areas - one from the center of the shot, the other from the corner.