05-16-2011, 11:06 PM
[quote name='Bryan Conner' timestamp='1305578379' post='8380']
I would really like to have a method of making a fair determination of the focus performance of the lens. Should I photograph a newspaper (or something similar) attached to a wall to judge the performance? Or, is there a better method? I want the test to be as fair and as accurate as possible before I go through the process of sending it in to Sigma.
[/quote]
The procedure is described here in FAQ section. Also at BobAtkins.com are some hints (testing camera lenses). I think it is more valuable to test decentering or select the best copy if you have few, but to determine is the sharpness within specs by eye is really difficult. You can compare to another lens, but the results (better or worse) you may already know.
A.
I would really like to have a method of making a fair determination of the focus performance of the lens. Should I photograph a newspaper (or something similar) attached to a wall to judge the performance? Or, is there a better method? I want the test to be as fair and as accurate as possible before I go through the process of sending it in to Sigma.
[/quote]
The procedure is described here in FAQ section. Also at BobAtkins.com are some hints (testing camera lenses). I think it is more valuable to test decentering or select the best copy if you have few, but to determine is the sharpness within specs by eye is really difficult. You can compare to another lens, but the results (better or worse) you may already know.
A.