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01-06-2010, 02:33 PM   #16
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QuoteOriginally posted by Big G Quote
It's going to die. After it dies on you a couple of times, you can probably resuscitate it--but eventually, it just dies dead.

01-06-2010, 03:34 PM   #17
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QuoteOriginally posted by asdf Quote
It's going to die. After it dies on you a couple of times, you can probably resuscitate it--but eventually, it just dies dead.
I agree with asdf here. Sorry for your loss. This maybe the first stages of SDM death on your lens, I am sorry to say. The 70mm case looks like plain-old slow and jerky SDM+Pentax body AF. The 17mm is like nothing I have ever seen before.

Time for a refund. Stop playing SDM roulette and you'll be happier. No more nagging little voice in the back of all SDM shooters' heads when taking an important shot saying: "is this the time when my SDM will fail?"

Thanks for posting your videos here though. I wish I would have been smart enough to do that with the previous two da* 50-135's. Maybe if we had a "database" of videos showing how SDM failed on each, we (or Pentax) could learn something helpful.

Last edited by PentaxPoke; 01-06-2010 at 03:45 PM.
01-06-2010, 03:52 PM   #18
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Yep, it's going back to Pentax.

Just for comparison, here is my Sigma 100-300mm f/4 EX DG.



Considering that's a K20D, it's very quick and snappy indeed with razor sharp images to boot. The Sigma 10-20mm is just as quick. Anything slower than that will not do - does anyone know how Sigma HSM lenses perform? If it's better than Pentax SDM, I could be tempted by one of these babies:

Sigma 17-70mm f2.8-4 DC Macro OS HSM Lens - Pentax Fit (668961) - Warehouse Express
01-07-2010, 01:21 AM   #19
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QuoteOriginally posted by PentaxPoke Quote
Do you know what the LV was for that test simico?
Sorry, I have no idea... I did it in the evening, room was lit by one "energy-saver" fluorescent lamp (though its color temperature is actually close to tungsten). Usually I get 1/4 - 1/6 shutter speeds at f4 & ISO1600 under these conditions.

QuoteOriginally posted by Big G Quote
17mm:

Uhh, that's really bad, it screams "service time!!"
The 70mm video seems to be ok - usual Pentax SDM & AF speed...
What I really don't like in Pentax SDM (beside the obvious "SDM dies" issue) is that all of the screw-driven lenses I've tried focus much faster. SDM speed was quite disappointing after my kit lens' fast "zzzzip, beep" AF

QuoteOriginally posted by Big G Quote
does anyone know how Sigma HSM lenses perform? If it's better than Pentax SDM, I could be tempted by one of these babies:
Based on what I've heard and read from others, and what I've seen with my eyes: it seems to be better than SDM. True ring motors, fast and snappy AF.

01-07-2010, 02:10 AM   #20
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QuoteOriginally posted by PentaxPoke Quote
Maybe if we had a "database" of videos showing how SDM failed on each, we (or Pentax) could learn something helpful.
Hitler's SDM fails

(Well, I thought it was really funny. )
01-07-2010, 02:45 AM   #21
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QuoteOriginally posted by asdf Quote
Hitler's SDM fails

(Well, I thought it was really funny. )
That is hilarious. Whoever did that has really been following the boards.
01-07-2010, 02:51 AM   #22
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These Untergang edits are numerous, but this is definitely one of the better ones!
01-07-2010, 04:56 AM   #23
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QuoteOriginally posted by Big G Quote
Yep, it's going back to Pentax.
BTW, did you check the Sigma 10-20 at 17mm and with the same target?

QuoteQuote:
Anything slower than that will not do - does anyone know how Sigma HSM lenses perform?
Here's a video I made 7 months ago (Sigma 50 f/1.4):
http://www.youtube.com/watch?v=DEXkHmAzrRo

HSM is slightly louder, but it's still working after 7 months.

BTW, the SDM on my DA* 300 f/4 still works (knock on wood) and nobody's complaining about the reliability of the SDM on the primes *as much*.

Also, there is no quick-shift with the HSM lenses...although quick shift sometimes fails too. Here are some videos I found:
http://www.youtube.com/watch?v=NcQmj9xxVh0
http://www.youtube.com/watch?v=QAXwJFNBLgM

01-07-2010, 05:45 AM   #24
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Yeah, I plugged in the Sigma 10-20mm @ 17mm and it was the usual rapid Sigma behaviour - "zipppp, beep!".

That's a good video adsf, I saw that one on Youtube when I was looking for HSM videos - is it possible you could make another video that shows it locking onto a target from a defocussed infinity state? I'd like to see if Sigma HSM is like the Pentax SDM's "sweeeeep, click, adjust, click, adjust, beep" or if behaves like their screw driven lenses.

There is quite a lot of talk surrounding Sigma's latest 17-70mm f/2.8-4 OS HSM over on dpreview, I might sell my 17-70mm Pentax in favour for it given my pleasure with my current Sigma line up.

New Sigma 17-70mm F2.8-4 DC Macro OS HSM [Page 1]: Pentax SLR Talk Forum: Digital Photography Review
01-07-2010, 05:54 AM   #25
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Has everyone noted Peter Zack's breakthrough?
01-07-2010, 06:04 AM   #26
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Yes, but shorting pins or having SD over SDM isn't really of interest to me though. I'd much prefer to get my lens fixed.
01-07-2010, 08:21 AM   #27
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QuoteOriginally posted by Big G Quote
Yes, but shorting pins or having SD over SDM isn't really of interest to me though. I'd much prefer to get my lens fixed.
Of course.
.
01-08-2010, 02:26 AM   #28
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QuoteOriginally posted by Big G Quote
Yes, but shorting pins or having SD over SDM isn't really of interest to me though. I'd much prefer to get my lens fixed.
Not to mention that 17-70 has KAF3 mount, so there's no screwdrive AF.
01-08-2010, 02:57 AM   #29
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Right - forget about shorting the SDM circuit on the camera to screwdrive the 17-70 - it has no screw to drive... then again, what you're experiencing Big G is clearly not normal. You'd be much more impressed with a properly functioning 17-70...
01-09-2010, 01:10 PM   #30
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Sent my lens back to the retailer today to send to Pentax, I'll keep you posted on how this pans out.
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