[Gerdis]

Всем привет!
Вчера прислали новый объектив - SMC-DA* 60-250mm, установил на К-7 и -увы! - не работает автофокус... У кого-нибудь были проблемы с автофокусом на DA* объективах? Может, нужно поменять установки на камере (это мой первый объектив с SDM - опыта нет). Буду благодарен за совет и помощь, спасибо

[Hello_Photo]

Expect lots of discussion on this one. I'll try to summarize:

There have been numerous reports from individuals of the SDM AF mechanism failing in various DA* lenses. The primary symptoms have been no, or exceptionally slow response to attempts to us AF (e.g. shutter release button half-pressed and lens takes 10 or more seconds to respond). Suffice it to say that there have been more reports from owners of the more popular lenses (notably, the DA* 16-50 and the DA*50-135). While it has been acknowledged that any electronic mechanism that is mass-produced will have a failure rate greater than zero, there is heated debate regarding whether Pentax SDM failure rates are excessive, compared with other manufacturers with similar technologies (Nikon's AF-S, Canon's USM, Sigma's HSM and Sony's SSM). There have been various surveys taken in an attempt to quantify the frequency of these failures. However, the statistical validity of these surveys has been called into question on the basis of sampling bias - those with problems are more likely to participate in these discussions/surveys than those without. To my knowledge, Pentax has never publicly acknowledged any problems associated with the SDM technology itself. Rather, failures have been treated as isolated incidents, with repairs made under warranty (if the failure occurred during the warranty period). This has frustrated numerous Pentax owners, who have experienced SDM failures shortly outside the warranty period (1 year in the US, 2 years in Canada, not sure about Russia). Often, the sufficiency of the warranty period is called into question, as other manufacturers have longer warranty periods on their "professional" lenses.

With that out of the way, I think the first step for you is to rule-out any problems with the settings and set-up of your camera:
1) Verify that the AF mode switch on camera body is set to "AF-C" or "AF-S"
2) Verify that the AF mode switch on the lens is set to "AF"
3) Inspect and clean the electrical contacts between the lens and camera body to ensure a good connection.
4) Ensure that you have the AF function on the camera body set-up correctly. There is a custom menu option that allows you to engage the AF system when you half-press the shutter release button, or when you press the AF button on the back of the camera. Make sure this setting is consistent with how you expect to engage the AF system.
5) Since you have a K-7, no firmware updates are necessary - on the K10D, only v1.30 supports SDM and earlier Pentax models do not support SDM at all (they default to screw-drive AF).

Best of luck!

[sinus007]

Hi Gerdis,
As HelloPhoto suggested, check the AF/MF switches on body and on the lens. If both are in AF, it's about 99% probability that you have to sent the lens for repair or exchange. Hopefully the lens is under warranty and/or you bought it from a reputable store.
Good luck.

[noahpurdy]

Does the 60-250 also have a screwdriver slot on the back of the lens, check to make sure the slot doesn't line up with the screwdrive on the body. I've had them lign up and cause the SDM to struggle before.

[Gerdis]

Dear noahpurdy,Your message was automatically translated into Russian and I cannot clearly understand what you mean (something to do with a screwdriver, perhaps?). Can you send me your suggestions in English please?