نقل قول:
In the field I had more occasions where phase-detect AF did not lock correctly on target than I normally encounter. It seemed to be a spurious error and I couldn't find a clear pattern. But it was pretty annoying that I had to check each and every shot for correctly acquired auto-focus. Therefore I did another series of 100 specific test-shots at f1.4 on various natural targets at good light and found 75% to be in very good focus, 20% a bit off visible only at 100% magnification, and 5% real outliers visible even at only 25% magnification. Again this experience was when using the lens on my Nikon D810 - your mileage may vary on other bodies and brands.
دومين مورد درباره لنز 15-30 تمرون هست كه در اين لنز هم عدم يكنواختي نسبتا خوبي! در زمينه اتوفوكوس مشاهد مي گردد: