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04-15-2011, 11:04 AM   #16
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The biggest thing about Sigma lenses is their size. They really can be huge compared to equivalent Pentax lenses. The new Sigma 50-150 is equivalent pricing to the DA *50-135, so no big break there. The only benefit I can see is a little faster auto focus.

04-15-2011, 12:08 PM   #17
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Why not get the best of both worlds; nobody says that you are not allowed to mix and match to your needs. Sigma (or Tamron) 70-200 instead of DA*50-135 gives you the reach. Add FA31Ltd as standard lens and Sigma 10-20 (or DA12-24 or DA15Ltd) for the wide side.

QuoteOriginally posted by veezchick Quote
Although, I suspect the 50mm "limit" with 2 lenses could get cumbersome.
I've solved that for you by not buying a standard zoom. Serious, if you're worried about that, you're better off with a Tamron 18-270 (from that perspective).
04-15-2011, 03:52 PM   #18
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QuoteOriginally posted by Rondec Quote
The biggest thing about Sigma lenses is their size. They really can be huge compared to equivalent Pentax lenses. The new Sigma 50-150 is equivalent pricing to the DA *50-135, so no big break there. The only benefit I can see is a little faster auto focus.
I don't think size is an issue since you are getting a zoom. zooms tend to be bigger so it's pretty much accepted as a compromise. it would had been different though if we were comparing primes on the other hand.
04-16-2011, 09:24 AM - 2 Likes   #19
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Do not feed Pentax's incredible arrogance on the SDM design flaw by buying those lenses. Boycott SDM.

04-17-2011, 07:45 AM - 1 Like   #20
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Oh Please

QuoteOriginally posted by tarsus Quote
Do not feed Pentax's incredible arrogance on the SDM design flaw by buying those lenses. Boycott SDM.

I have had lenses with SDM for over a year now with no problem. There are flaws with every camera makers lenses. Such a generalization is ridiculous.
04-17-2011, 08:29 AM   #21
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I've looked at Sigma lenses a lot over the years, but always shied away from getting any.

Case in point the Pentax 12-24 mm vs the Sigma 10-20mm.

The Sigma has 2 mm more at the wide angle extreme and that's an advantage.

But the Pentax 12-24mm has great ratings, Popular Photography, if memory serves said best in class.

It is very expensive, at least in Canada.

I bought the Pentax 12-24 and boy am I happy with this very fine, high quality lens.

Not sure if you can rent them first, before you make your choice.
04-17-2011, 08:50 PM   #22
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The SDM design flaw is not a generalization. It is a fact based on solid evidence from numerous users who report multiple failures. Search the forum. If you are willing to call those who made such reports liars, have at it. It is not the flaw that is the problem. As you correctly say, every system has its problems. It is Pentax refusing to acknowledge the problem and provide meaningful relief. Boycott SDM.
04-17-2011, 09:08 PM   #23
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QuoteOriginally posted by tarsus Quote
The SDM design flaw is not a generalization. It is a fact based on solid evidence from numerous users who report multiple failures. Search the forum. If you are willing to call those who made such reports liars, have at it. It is not the flaw that is the problem. As you correctly say, every system has its problems. It is Pentax refusing to acknowledge the problem and provide meaningful relief. Boycott SDM.
I don't have to call them liars. I can point at the many users that have no issue with their SDM lenses, and suggest that you don't have a statistically significant sample to start inferring corporate malfeasance on the part of Pentax. My own 50-135 works very well, a year and a half old. Wait, two years old. It's well known that people who have problems are more likely to complain than people who don't are likely to ... "anti-complain".

04-17-2011, 11:19 PM   #24
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QuoteOriginally posted by jstevewhite Quote
I don't have to call them liars. I can point at the many users that have no issue with their SDM lenses, and suggest that you don't have a statistically significant sample to start inferring corporate malfeasance on the part of Pentax. My own 50-135 works very well, a year and a half old. Wait, two years old. It's well known that people who have problems are more likely to complain than people who don't are likely to ... "anti-complain".
why consumers are weary about SDM technology by Pentax?

these are the possible reasons I can think of:

1.> SDM failure don't show during the initial period of use. it is more highly likely that when Pentax designed or tested the product, they haven't really thought that such a problem would arise after a certain period of time. therefore, it is a different area of tolerance which Pentax could had possibly didn't think would happen.

2.> Pentax warranty only covers 2 years (1 year on others). the problem occurs near or after the end of the warranty period.

3.> acknowledging a fault in the system would be devastating especially for a small end market like Pentax. less confidence in the system at the same time bad PR.

4.> a massive recall means millions lost in costs and revenues. repair and replacement is cheaper especially if the consumer pays for it.

5.> the lack of answer coming from Pentax. Pentax does not confirm nor deny the existence of SDM failure. how difficult is it to get an answer from Pentax if such thing does is just a pigment of a person's imagination.

6.> failure means back to the drawing board for Pentax. means higher costs and faster time for R&D.

7.> HSM is just better.

8.> not all Pentax users are PF forum members. so who knows what is out there not being reported could be a lot worse.


so what's the difference between the SDM and the K-5 issues. K-5 flash issue is more of firmware based. the sensor stain (immediate problem) can be solved by a new production line. no necessary changes in design that would cost more money. also, there is now way Pentax would simply ignore their flagship camera's issue at it's launch period, not to mention it affects the image.


to those who own the DA* zooms and are still reliable, we are happy for you. if there are people that don't prefer them, they would probably atleast one of the factors mentioned.
04-18-2011, 02:23 AM   #25
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QuoteOriginally posted by KLSMpls Quote
Whatever you decide, I would include the Pentax 50 - 135. It is simply stellar and the reviews support my opinion. My best piece of glass and perfect for portraits.
The DA*50-135 has been my most used lens since I bought it last October. I only regret not buying it sooner.
04-18-2011, 06:51 AM   #26
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QuoteOriginally posted by Pentaxor Quote
why consumers are weary about SDM technology by Pentax?
I don't think consumers *are* wary of SDM technology. I think *some forum members* are wary of SDM technology.

QuoteQuote:
1.> SDM failure don't show during the initial period of use. it is more highly likely that when Pentax designed or tested the product, they haven't really thought that such a problem would arise after a certain period of time. therefore, it is a different area of tolerance which Pentax could had possibly didn't think would happen.
This is a good observation, but not germane to the question of whether "SDM Failure" constitutes corporate malfeasance on Pentax's part.

QuoteQuote:
2.> Pentax warranty only covers 2 years (1 year on others). the problem occurs near or after the end of the warranty period.
Same as above.

QuoteQuote:
3.> acknowledging a fault in the system would be devastating especially for a small end market like Pentax. less confidence in the system at the same time bad PR.

4.> a massive recall means millions lost in costs and revenues. repair and replacement is cheaper especially if the consumer pays for it.
You've not shown such a recall is necessary. I know five or six Pentax shooters who own SDM lenses and not one of them has had "SDM failure". Neither my anecdote, nor the complaints on these forums, constitutes statistical *data*. The plural of anecdote is not "data".

QuoteQuote:
5.> the lack of answer coming from Pentax. Pentax does not confirm nor deny the existence of SDM failure. how difficult is it to get an answer from Pentax if such thing does is just a pigment of a person's imagination.

6.> failure means back to the drawing board for Pentax. means higher costs and faster time for R&D.
There's no proof Pentax owes anyone an answer on this topic. And Pentax had *better* have people sitting at that drawing board all day long, every day. They have a new motor technology already (DC motor).

QuoteQuote:
7.> HSM is just better.
That may be true... so?

QuoteQuote:
8.> not all Pentax users are PF forum members. so who knows what is out there not being reported could be a lot worse.
Or a lot better, which is my point. The forums here are a self-selecting group, not a random group, and as such do not constitute "representative samples" of Pentax users.

QuoteQuote:
so what's the difference between the SDM and the K-5 issues. K-5 flash issue is more of firmware based. the sensor stain (immediate problem) can be solved by a new production line. no necessary changes in design that would cost more money. also, there is now way Pentax would simply ignore their flagship camera's issue at it's launch period, not to mention it affects the image.
??? How do those relate to the "SDM failure"? Or are you offering them as more examples of "Pentax malfeasance"?

QuoteQuote:
to those who own the DA* zooms and are still reliable, we are happy for you. if there are people that don't prefer them, they would probably atleast one of the factors mentioned.
And I'm sorry that your SDM lens failed, honestly. And I completely "get" people thinking about complaints that they've seen in the forums when purchasing a thousand dollar lens. On the other hand, the DA* 50-135 is one of the best zoom lenses around, bar none, which was my point initially; and I suspect that the vast majority of SDM lenses do *not* fail.
04-18-2011, 07:42 AM   #27
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Thx JSteveWhite. Exactly!
04-18-2011, 07:53 AM   #28
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QuoteOriginally posted by jstevewhite Quote
I don't think consumers *are* wary of SDM technology. I think *some forum members* are wary of SDM technology.



This is a good observation, but not germane to the question of whether "SDM Failure" constitutes corporate malfeasance on Pentax's part.



Same as above.



You've not shown such a recall is necessary. I know five or six Pentax shooters who own SDM lenses and not one of them has had "SDM failure". Neither my anecdote, nor the complaints on these forums, constitutes statistical *data*. The plural of anecdote is not "data".



There's no proof Pentax owes anyone an answer on this topic. And Pentax had *better* have people sitting at that drawing board all day long, every day. They have a new motor technology already (DC motor).



That may be true... so?



Or a lot better, which is my point. The forums here are a self-selecting group, not a random group, and as such do not constitute "representative samples" of Pentax users.



??? How do those relate to the "SDM failure"? Or are you offering them as more examples of "Pentax malfeasance"?



And I'm sorry that your SDM lens failed, honestly. And I completely "get" people thinking about complaints that they've seen in the forums when purchasing a thousand dollar lens. On the other hand, the DA* 50-135 is one of the best zoom lenses around, bar none, which was my point initially; and I suspect that the vast majority of SDM lenses do *not* fail.
if people are looking for a silent AF mechanism, there is no point on purchasing a slower one, and tainted reliability.

also, it would be funny to think that Pentax came up with a new DC motor without having to explain anything what happened to SDM. so it's more of a Pentax malfeasance as well.
04-18-2011, 08:09 AM   #29
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QuoteOriginally posted by Pentaxor Quote
if people are looking for a silent AF mechanism, there is no point on purchasing a slower one, and tainted reliability.

also, it would be funny to think that Pentax came up with a new DC motor without having to explain anything what happened to SDM. so it's more of a Pentax malfeasance as well.
I dunno about you, but I buy my lenses based primarily on the quality of image they produce. The 50-135 is beyond reproach, and, in my experience, exceptional. Not just good, but *great*. For me, that's more important than a slightly faster focusing system.

So now you're suggesting that introducing a new technology after THREE YEARS is suspicious? I think the biggest knock against SDM is that it's a little long in the tooth and due for a replacement. It's a sign of continuing investment in R&D, and you want to paint it as a corporate scam?
04-18-2011, 08:25 AM   #30
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QuoteOriginally posted by jstevewhite Quote
I dunno about you, but I buy my lenses based primarily on the quality of image they produce. The 50-135 is beyond reproach, and, in my experience, exceptional. Not just good, but *great*. For me, that's more important than a slightly faster focusing system.

So now you're suggesting that introducing a new technology after THREE YEARS is suspicious? I think the biggest knock against SDM is that it's a little long in the tooth and due for a replacement. It's a sign of continuing investment in R&D, and you want to paint it as a corporate scam?
the issue here is not IQ, but AF reliability. if one was looking for IQ, then that's great. but it would be insane to think that people would pay extra for a non-working AF. better make it an mf lens instead sold for half the price, that would make more sense.

personally, it's a scam. you send emails and call customer support for help and they can't even give you a decent answer. how is it difficult to answer a question with a basic Yes or No ? so you can't blame people if they start to become suspicious or uneasy with a question that is left for themselves to answer.
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