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05-30-2010, 08:25 AM   #16
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I wonder how it would fare in a body with a weaker focusing motor (K-x, other AA battery bodies), although there is that new Algorithm which probably improves the slower lens more.

Too bad we can't try it out.


Last edited by Eruditass; 05-30-2010 at 08:52 AM.
05-30-2010, 08:36 AM   #17
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I have read here on the forums that the camera is not "fooled" by taping over the SDM contacts. A few members have (two, at least) K20Ds that won't use the SDM , and defaults to screw drive. This is probably due to the SDM electronics being shorted and broken.

My guess is that the "digital info contact" in the KAF2 mount supplies information on whether to use SDM or screw drive. Insulating this won't work, though, and disables a lot of other information needed for the body.

Last edited by KjetilH; 05-30-2010 at 09:00 AM.
05-30-2010, 12:31 PM   #18
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AFAIK the two contacts only supply power for the SDM motor. The actual data is transmitted over the appropriate contact on the lens mount.

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06-05-2010, 08:52 AM   #19
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But what does it do, when it gets no power? Isn't it the same as if SDM circuit was down. Or it simply stays in SDM mode but wont focus.

06-06-2010, 01:17 PM   #20
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QuoteOriginally posted by ytterbium Quote
But what does it do, when it gets no power? Isn't it the same as if SDM circuit was down. Or it simply stays in SDM mode but wont focus.
The latter, I believe.
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