Lens review
2009-06-05
Leica D Summilux 25 mm f/1.4
7. Coma and astigmatism
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It is obvious that the next reason of the weak frame edge performance is coma, which, at maximum relative aperture, is very visible indeed. Fortunately when you stop down to f/2.0 it decreases to a minimum level. Here again the Leica fares worse than the Olympus primes but very similarly to the Canon 1.4/35.
The astigmatism level is average because the typical differences between horizontal and vertical MTF50 function values reached 11% in our test.
