Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
07-11-2012, 11:51 AM   #46
Site Supporter




Join Date: Mar 2009
Location: Gladys, Virginia
Photos: Gallery
Posts: 16,249
QuoteOriginally posted by Docrwm Quote
Rob,
Exactly. I would add that if you look at the Zooms apart from the Primes with SDM the picture is clearer that SDM + Zoom = serious design/manufacture problems.
The hard part is that analyzing it, I would be willing to bet that there are significantly higher numbers of 16-50 and 50-135 lenses sold than any of the DA * primes (or the 60-250).

07-11-2012, 11:56 AM   #47
Veteran Member
Docrwm's Avatar

Join Date: Sep 2010
Location: Somewhere in the Southern US
Photos: Gallery | Albums
Posts: 11,275
QuoteOriginally posted by Rondec Quote
The hard part is that analyzing it, I would be willing to bet that there are significantly higher numbers of 16-50 and 50-135 lenses sold than any of the DA * primes (or the 60-250).
I believe that you are right. However, if you do a class analysis SDM vs. DC you see a startling result - 0 vs. 100+ failures. It's not the complexity of the process, remember that the DC came out after Pentax had the chance to analyze all the SDM failures. I think they did a good job - from an engineering standpoint - of fixing the original problem. The real error has been saying that there isn't a design fault with the SDMs.
07-11-2012, 12:20 PM   #48
Moderator
Tom S.'s Avatar

Join Date: May 2008
Location: S.E. Michigan
Photos: Albums
Posts: 4,239
QuoteOriginally posted by Anvh Quote
Ah yes in such a way, well sorry that you live in the USA maybe it's time to move?
Move to Europe? No thanks! Members of my family have already been there twice to help stop your World Wars.
07-11-2012, 12:52 PM   #49
Veteran Member
Anvh's Avatar

Join Date: Sep 2011
Posts: 4,616
That's many years ago, things have changed you know

07-11-2012, 02:28 PM   #50
Moderator
Tom S.'s Avatar

Join Date: May 2008
Location: S.E. Michigan
Photos: Albums
Posts: 4,239
QuoteOriginally posted by Anvh Quote
That's many years ago, things have changed you know
Yeah, now you're working to bail out the "pigs" Portugal, Italy, Ireland, Greece and Spain. Good luck with that Euro thing.
07-11-2012, 02:42 PM   #51
Veteran Member
Docrwm's Avatar

Join Date: Sep 2010
Location: Somewhere in the Southern US
Photos: Gallery | Albums
Posts: 11,275
QuoteOriginally posted by Tom S. Quote
Move to Europe? No thanks! Members of my family have already been there twice to help stop your World Wars.
Don't forget stopping the Communists and freeing Eastern Europe with our wrong-headed nuclear and military policies under Reagan too.
07-11-2012, 03:06 PM   #52
Veteran Member




Join Date: Jan 2007
Location: New Mexico
Photos: Albums
Posts: 1,125
QuoteOriginally posted by Anvh Quote
Ur saying they are putting the old type of SDM in the lenses, sounds a bit strange to me.
That is what I was told by someone at Pentax USA. I was stunned to learn that they are replacing a defective mechanism with the the identical mechanism, but that would explain the rash of people who have experienced second and even third SDM failures. One would have hoped that Pentax would perform the repairs using upgraded parts, but perhaps the flaw is in the basic design of the SDM and, thus, is not fixable in a permanent way. If that is, indeed, the case, Pentax would garner buckets of good will by offering a lifetime warranty for any SDM unit that they repair. Oh, wait, that might hurt quarterly profits, which makes it unthinkable, even if it would enlarge the base of loyal customers.

Rob
07-11-2012, 03:16 PM   #53
Veteran Member




Join Date: Jan 2007
Location: New Mexico
Photos: Albums
Posts: 1,125
QuoteOriginally posted by Docrwm Quote
Don't forget stopping the Communists and freeing Eastern Europe with our wrong-headed nuclear and military policies under Reagan too.
My how this thread has taken a nasty, jingoistic turn that is beyond "off topic". Let's keep things civil and get back to discussing things that are at least remotely related to photography.

Rob

07-11-2012, 03:26 PM - 1 Like   #54
Veteran Member
Docrwm's Avatar

Join Date: Sep 2010
Location: Somewhere in the Southern US
Photos: Gallery | Albums
Posts: 11,275
QuoteOriginally posted by robgo2 Quote
My how this thread has taken a nasty, jingoistic turn that is beyond "off topic". Let's keep things civil and get back to discussing things that are at least remotely related to photography.

Rob
I don't tolerate Anti-Americanism, however vogue or hip it is, from anyone. There is a pattern with some members here of taking shots at the US whenever they can. Also, look for the beginning, please don't quote out of context. Oh, and that is Civil, perhaps not to your taste but it's civil.

Last edited by Docrwm; 07-11-2012 at 03:42 PM.
07-11-2012, 04:09 PM   #55
Veteran Member




Join Date: Jan 2007
Location: New Mexico
Photos: Albums
Posts: 1,125
QuoteOriginally posted by Docrwm Quote
I don't tolerate Anti-Americanism, however vogue or hip it is, from anyone. There is a pattern with some members here of taking shots at the US whenever they can. Also, look for the beginning, please don't quote out of context. Oh, and that is Civil, perhaps not to your taste but it's civil.
My comments were not directed only at you, but at all the snipers in this thread. However, it does seem to me that some people cannot distinguish between good natured kidding and a genuine insult. That's called being overly sensitive. I think that may be how wars sometimes get started.

I will repeat: Let's get back to photography.

Rob

Last edited by robgo2; 07-13-2012 at 04:57 PM.
07-11-2012, 04:15 PM   #56
Veteran Member
Docrwm's Avatar

Join Date: Sep 2010
Location: Somewhere in the Southern US
Photos: Gallery | Albums
Posts: 11,275
QuoteOriginally posted by robgo2 Quote
My comments were not directed only at you, but at all the snipers in this thread. However, it does seem to me that some people cannot distinguish between good natured kidding and a genuine insult. That's called being over sensitive. I think that may be how wars sometimes get started.

I will repeat: Let's get back to photography.

Rob
Thanks, but you quoted me. Also, my point stands that it was not a reaction to a single post but to a pattern of posts. Genuine insults, and ongoing digs, are not ok -even if only directed at the US.
07-11-2012, 04:51 PM   #57
Pentaxian
twitch's Avatar

Join Date: Nov 2009
Posts: 4,571
QuoteOriginally posted by Anvh Quote
Ur saying they are putting the old type of SDM in the lenses, sounds a bit strange to me.
There is no new type, there is only the "old" type. I know the post you are refering to when Ben thought he'd received better replacement SDM motor in his lens, however he has since realised they weren't better and that replacement SDM has since failed him again. At the time the whole new SDM thing was merely speculation, there was no hard evidence for it and it has since proven to be a false hope.

We still have the same SDM-POS we always had. We can only hope DC (or better) becomes the standard for any new lenses.
07-11-2012, 05:20 PM   #58
Pentaxian
normhead's Avatar

Join Date: Jun 2007
Location: Near Algonquin Park
Photos: Gallery | Albums
Posts: 25,864
Amazing that Pentax can have two dud lenses with very high failure rates... and still lead the pack, overall in terms of initial quality. Those other camera companies must have some real duds.

I've never been tempted to purchase either the 15-50 or the 50-135... I guess what you guys are saying is don't ever get tempted. What ever the pblem is, and just from this thread it's beginning to dawn on me that perhaps the problem isn't SDM. Perhaps the problem is the mechanics of the 16-50 and 50-135. Sloppy tolerances in the gear train/ clutch etc, could cause a motor failure. TIghtening up a few tolerances in manufacture would possibly fix that. Putting in the same SDM motor you took out wouldn't.
07-11-2012, 05:29 PM   #59
Veteran Member
Docrwm's Avatar

Join Date: Sep 2010
Location: Somewhere in the Southern US
Photos: Gallery | Albums
Posts: 11,275
QuoteOriginally posted by normhead Quote
Amazing that Pentax can have two dud lenses with very high failure rates... and still lead the pack, overall in terms of initial quality. Those other camera companies must have some real duds.

I've never been tempted to purchase either the 15-50 or the 50-135... I guess what you guys are saying is don't ever get tempted. What ever the pblem is, and just from this thread it's beginning to dawn on me that perhaps the problem isn't SDM. Perhaps the problem is the mechanics of the 16-50 and 50-135. Sloppy tolerances in the gear train/ clutch etc, could cause a motor failure. TIghtening up a few tolerances in manufacture would possibly fix that. Putting in the same SDM motor you took out wouldn't.
It's actually more than 2 dud lenses. Must say something about how bad the others are with their design and QC.
07-11-2012, 07:48 PM   #60
Pentaxian




Join Date: Nov 2011
Photos: Gallery | Albums
Posts: 3,735
QuoteOriginally posted by Docrwm Quote
Don't forget stopping the Communists
SDM lenses are assembled in a communist country:

https://www.cia.gov/library/publications/the-world-factbook/geos/vm.html
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
k-mount, pentax lens, sdm, sdm failure rate, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
What is a SDM failure like? slackercruster Pentax SLR Lens Discussion 6 04-25-2012 01:18 PM
Beginnings of SDM failure? krypticide Pentax SLR Lens Discussion 11 08-01-2011 11:35 AM
Is this Pentax way of admitting SDM was a failure? mfdesalas Pentax SLR Lens Discussion 49 12-28-2010 11:34 PM
DA* 50-135 SDM failure pattern? yusuf Pentax SLR Lens Discussion 7 10-15-2010 10:00 AM
SDM DA* failure rate as of October 2009? McLovin Pentax SLR Lens Discussion 7 10-13-2009 04:41 PM



All times are GMT -7. The time now is 05:16 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top