LensTip.com

Lens review

Olympus Zuiko Digital 11-22 mm f/2.8-3.5

4 December 2009
Arkadiusz Olech

7. Coma and astigmatism



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Looking at the following crops, taken from the frame centre and corner and showing the circular diode image, we can see that the coma is bothersome at all focal lengths and it contributes towards the worsening of the image quality at the edge.

Olympus Zuiko Digital 11-22 mm f/2.8-3.5 - Coma and astigmatism

The same thing is true when it comes to the astigmatism, which average value for all focal lengths amounts to 9%. You can notice, though, that in the middle of the range the value is the lowest (only 5%) and it increases significantly at the extreme ends (11%).