LensTip.com

Lens review

Sony FE 50 mm f/1.8

24 November 2017
Maciej Latałło

10. Autofocus


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When the autofocus is active you can hear a slight buzz of the motor. The sound might be not bothersome but it is far from noiseless performances of good quality ultrasonic motors. The autofocus is also slow – running through the whole distance scale and finding the proper position takes about one second. What’s more, when the lens is strongly defocuses it happens from time to time that the motor moves in the right direction, slows down, turns back, realizes that it is a wrong direction, turns back again and finds the focus only afterwards. Such ‘focus hunting’ happens not only in bad lighting conditions but also in good ones. As we made sure both the lens and the camera body had had the newest software installed there are simply no excuses; we cannot asses such a performance positively.

When it comes to the accuracy of the mechanism we had no reservations concerning only the static shooting in the studio. The accuracy was very good, with small angle scattering of results. During the outdoor sessions we noticed far more misses; these were especially surprising as they happened during the handheld series of photos for the same frame position. Most of photos were sharp but from time to time the lens had a huge miss for unknown reasons.

The shot below proves that the tested lens had also a slight back focus tendency, aiming at an area right behind the photographed object. It was important only when you took photos from the minimum focusing distance. For greater distances the photographed object usually fitted the depth of field range even at the maximum relative aperture so the problem stopped being serious.

A7R II, f/1.8
Sony FE 50 mm f/1.8 - Autofocus