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07-07-2010, 04:12 PM   #1
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Coincidence? ( adjusted back focus and then DSM ies on 50-135mm )

I'm not happy......

I spent all day taking pictures of Yvon's focus charts ( excellent addition to an enthusiasts arsenal ) and then downloading the debug / older version firmware into my K10.
I have a lot of dyslexia and learning difficulties, so no matter how often I read the instructions and advice you guys posted it still took me nearly 3 hours to get into 'debug mode', but I did and adjusted the camera until I was satisfied with the focusing on the 18-55 kit lens and the DA 50-135.

I left the camera in debug and went into the graveyard behind our house ( it's a church, I'm not a serial killer ) which is a great place to check focusing and D.O.F. with both lenses.

The DA worked superbly, for a while. Then it hunted badly and then started to focus from the screw drive in the camera.

I then loaded version 3.1 firmware back into the camera, the focus adjustment have remained as I set them, but the SDM is still not working, although the screw drive has at least stopped hunting.

Have I screwed something up? or is it just coincidence that my SDM chose today to die?

I have barely used this lens, although it is now nearly 2 years old and out of warranty.
I'm so pissed off..............

07-07-2010, 04:15 PM   #2
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I'm assuming you're using a K10? If you're indeed using firmware 1.3, then there shouldn't be a problem. The only thing I could suspect is that an option in the debug mode could have disabled the SDM.

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07-07-2010, 04:37 PM   #3
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Out of the failed SDM posts i have read, i don't recall any that said that the screw focus started working when it failed.

I would recharge your batteries and try it again, perhaps after exercising the lens in manual mode a bunch.

The good news is that poster benjikan reported that he preemptively sent his 2 SDM lenses into the French repair center for installation of the upgraded SDM motors. After he got them back, he reported they focused faster than before. 2 other posts have made similar statements. So they know how to repair them now.

If you do send your lens in, you might consider sending them the camera plus the lens combo so they can sort out the problem, if its not the lens.

Sorry about the experience,
07-07-2010, 05:17 PM   #4
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I'd like to point out that, as I've understood, the lenses can't switch to SD instead of SDM, but the body actually can (as the lens probably just goes with the body). I don't remember who, but at least one K20D exhibited such behaviour after a shortage (?) of the SDM system.

Anyway, this could be interesting if you indeed provoked the change somehow. I would suggest asking in a shop (preferably where you bought the lens, of course) to see how the lens behaves on another body, before sending something in.

07-07-2010, 07:14 PM   #5
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I'm with the others here. When the SDM fails on the Lens, the lens will not Autofocus At All, not even screw drive. I'm sure there are people here who would love to know how you managed that (because their SDM has failed and they don't want to pay to fix it).

Try going back to FW 1.10 that you used to enter debug (I assume that's how you did it), and then load FW 1.30 (not 1.31) which is the original firmware that turns on SDM.

07-08-2010, 12:58 AM   #6
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Just bury your lens in the graveyard...

(sorry, couldn't resist)
07-08-2010, 02:37 PM   #7
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However tempting "burying the lens in the graveyard" was, I resisted.

And probably for the best.
I agree with you guys, the SDM hasn't just given up and the screw drive just started all on its own. but I believe it has got noisier.

After the hunting it seemed all to hell, noisy and unable to fix on a focus. I tried for a short while then gave up, it had been a difficult day.

Anyway, today I tried it again and the lens seemed OK but noisier than I remembered it, but it's a different noise to the 18-55 kit lens and the SMC 35-70 F Series lens that I have, so not having any other way to tell which focusing mechanism is at work I'm accepting it's the SDM on the DA 50-135.

Whether it is actually noisier than before I'm not 100% sure of now, but I'm suspicious that it is. Hopefully it's not on it's way out.

But, the good news is, I'm very pleased with the focus adjustment.
I took the lens for a walk today and sat by the river in the sun taking pictures of cygnets and ducklings. And on the way back I stopped for ice cream and beer, not together, there was a respectable pause between the two.

So here's a couple of pic's to make everyone go "Ahhhhh"

And a local Buddah, because I feel all nice and calm again

Thanks for the advice and help guys, it makes a difference.

Last edited by Lloydy; 07-08-2010 at 02:40 PM. Reason: wrong pic.
07-08-2010, 02:41 PM   #8
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Having the SDM failure before the warranty expires is probably not that bad at all. I have both DA* 16-50mm and 50-135mm and not having any problems. The warranty will expire in October... keeping my fingers crossed, if it fails, better before that expiry date.


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