Lens review

Canon EF 50 mm f/1.2L USM

10. Autofocus

The autofocus of the tested lens, as it befits a good USM motor, works practically noiselessly. The lens is not flash-quick, though. On the EOS 1Ds MkIII it takes 1.0-1.1 second to run through the scale, no matter from what end. On the 50D the speed was even a bit worse.

When it comes to the accuracy, the autofocus was a tad more predictable working on the EOS 50D. In its case the number of misses in studio conditions reached a negligible level of 2%. On the 1Ds MkIII that percentage increased to 7%.

In the case of the EOS 50D the lens attached to the camera straight from the box showed a slight backfocus tendency. We managed to correct it without any problems from the camera’s menu level. There were no such surprises in the case of the 1 Ds MkIII.