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07-27-2009, 01:41 AM   #31
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QuoteOriginally posted by philbaum Quote
That's really odd. I assume that when you put other autofocus lenses on the K20d, they work fine. Which sort of says that the AF circuit on the K20d is fine???

Have you installed the lastest ver 1.3 firmware on the camera?

Do you have different batteries in K200 vice the K20 (of course, i just remembered the K200D has aa batteries) This kind of implies that battery voltage is making a difference. Try a freshly recharged battery in your K20D, or perhaps a different one.

Also, in an old thread on dpreview, there was a discussion on the DA 50-135/16-50 about how a coupla guys fixed their SDM problems by just cycling their AF circuits by focusing on something close, then something far away, and then repeating it several times. Apparently the problem got less and less and then went away.

Regards my only SDM lens, the DA*300, i've not had any problems wtih the SDM AF. It was bought in 2008 in the fall and is working fine. No hangups ever. I just focused on a brick wall in shade inside my house but sunny outside. It focused fine and locked all the way to aperture F22 at 0.7" shutter in AV, AFS. I tried at each aperture
Yes, using other non sdm lenses on k20 autofocus is FAST and reliable, no hunting.
Just now I was trying again with DA18-250, really fast always locking on the target and no hunting at all changing from focusing in infinity to 5 meters away etc.
Same testing with the DA*300 and problems occur specially when changing distances, for instance infinity to 5 meters away or the other way around, hunting a lot. Pressing AF button it spins looking for focus until it stops and nothing. I have to press again to restart the spin looking for focus until it gets it.
If I lock on a target at a specific distance and then go for other targets at more or less same distance it locks faster with no hunting (using AF-C)

On k200d, for now sdm is working properly and I already use different brands of rechargeable batteries. I just don't like to use it on k200d due to shooting speed/buffer

I bought DA300 with an extra fee for insurance, meaning I can during the first year of warranty send the lens back and get a refund to use on anything else I want to buy. So I will keep playing with the lens at least until October before I send it back or this sorts out.

07-27-2009, 11:00 AM   #32
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Forgot to say I had firmware 1.3 on k20d but even downgraded to 1.1 and give it a try and back to 1.3 and same thing, no sdm

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