LensTip.com

Lens review

Canon EF 17-40 mm f/4.0L USM

22 September 2007
Arkadiusz Olech

7. Coma and astigmatism

The next off axis distortion coma is corrected very well. At all focal lengths the diode point of the picture is only slightly distorted in the corner of the frame, which is not very problematic.

Canon EF 17-40 mm f/4.0L USM - Coma and astigmatism


The situation with astigmatism is similar. The average difference between the parallel and the horizontal resolution values measured in the center reaches 3.5%, which is a very good result.


Please Support Us

If you enjoy our reviews and articles, and you want us to continue our work please, support our website by donating through PayPal. The funds are going to be used for paying our editorial team, renting servers, and equipping our testing studio; only that way we will be able to continue providing you interesting content for free.

- - - - - - - - - - - - - - - - - advertisement - - - - - - - - - - - - - - - - -

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -