Sigma 35mm 1.4 Art - послесловие

у меня были две линзы Сигма 35мм 1.4 Арт. фазовый АФ - обе линзы прекрасно работают до 2м, большие проблемы с дистанциями 2- 5м -бесконечность- поправка сильно отличается. 

контрастный АФ - проблем нет. Линза великолепна по оптическим параметрам. 

Подробно о проблеме с АФ можно почитать на форумах дпревью, отзывах на сайте ВН, отзывах на яндексе. Вот типовые отзывы:

Focus problems at long end that can not be corrected with USB Lens Dock In reply to M J Valentine, Jun 14, 2013 
When I received my Sigma 35mm F1.4 Arts lens, I was impressed with the optics after I fixed the front focusing with MFA setting of +13. However, after a couple months of use, I noticed my landscape images weren't as sharp as when I was shooting people. When my Sigma USB Lens Dock arrived, I played with fine tuning my lens for hours. Now, I noticed there is something wrong/defective with the far end focus from 2m to infinity. At 2m end, MFA setting of +13 is needed but at infinity end, MFA setting of +7 is needed. Because 2m to infinity are in the same MFA section for this lens (using Sigma USB lens dock), I can only fix either 2m side or infinity side but not both. Worse yet, I noticed that the focus is not consistent, especially worse toward the infinity end. If I set my Canon 5D Mark III to AI Focus mode and try to focus on a stationary high contrast object close to the infinity end, focus will hunt non-stop. This problem still exist near the 2m end but not as bad. Everything else from 0.3m to 2m is working fine with consistent focus after applying MFA.

Infinity focus issues - Canon 5D MkIII, Sigma 35mm f/1.4 plus USB focus Dock - lens arrived with significant back-focus at Infinity, short distances good with the focus Dock initially set at 0,0,0,0. Camera body's lens micro-adjust set to +10 acheived remarkably Excellent sharpness (1', 1.5') and tight zone field at f/1.4,f/2.8. Other end of the scale is a totally different story: Dock adjusted to -5 at Infinity brings in the proper focus zone... but center sharpness is poor at f/1.4, f/2.8, doesn't clear up until f/5.6 and f/8 Using the MkIII's micro-adjust feature (+10 setting) delivers precise sharpness at 1' and 1.5' (with the Dock at "0, 0" first two zones). Trying to fix Infinity softness using the Dock, -5 focuses at the right distance but image is noticeably soft in the center, doesn't sharpen until f/5.6 or higher. Has anyone experienced an Infinity sharpness issue with this lens using a Canon body that also micro-adjusts? I can't figure out the right combination. Crisp sharpness at Infinity is a mandate.

сервис Сигмы - вежливый, компетентный. проблему признали сразу. признали что простого решения нет: 

- или они максимально точно настроят там где можно а остальное - переключаться в контрастный АФ/мануальный; 

- или вернут деньги; 

- или ждать ноября декабря новой партии (исправленной?);

линзы сейчас в сервисе не меняют, новая партия будет не ранее ноября/декабря. 

буду ли я покупать ее в в декабре из новой партии? не думаю. 

в 2015 выходит новый Canon 35 1.4. Очевидно, что недешевый, но гадать - сработал АФ нормально или нет или тем более фокусироваться только по лайв вью мне не хочется.