[Yamakasi]

i get a k-01

https://www.pentaxforums.com/forums/pentax-k-01/191080-new-purpose-k-01-reviv...autofocus.html

[Tom S.]

Another baseless SDM bashing thread.... a concept for you people. Buy only from dealers that offer extended warranties, and look at it as part of the purchase price of the lens. If that makes the lens too expensive, then move to another manufacturer that offers better warranties for less money. Or get Tamrons or other lenses that have better warranties.

SDM as an excuse for changing systems is just silly. People who are interested in changing systems can find better reasons than SDM, especially since there are so many non-SDM pentax lenses available.

SO what would you do if you experienced a motor failure on a Canon or Nikon system, would you then switch to Pentax? If that's the case, because of Pentax's small market share there would be a lot more people switching from Canon and Nikon than going the other way.

Oh , and I own an SDM lens and have never experienced a failure.. where's my check box? Oh ya, this isn't designed to be anything but a Canikon supporting Pentax bashing thread.

Norm, why should I need to buy an extended warranty on an item? In the course of the past 30 plus years, I have only bought an extended warranty on one purchase - my K5. The reason for that was the stain issue, and as it turned out, the money I spent for that warranty is pretty much wasted as my first K5 was replaced under the one year warranty and it's replacement has been flawless. My take on extended warranties is they should not be needed and amount only to a money maker for the retailer.

I am not bashing SDM, I am bashing Pentax's response, or lack there of, to the SDM problems. If Pentax issued a statement that there was a problem which has since been corrected, I would give SDM lenses a serious look. Without that assurance, I won't. Remember the old saying "Fool me once, shame on you, fool me twice, shame on me."? There will be no second time until I am sure I won't be fooled again (per Peter Townshend).

BTW: I did vote that I have no intention of leaving Pentax over this issue. I'll simply look for non-Pentax lenses to fill the voids.

[loco]

I have one SDM lens (DA*55) and I love that lens because it is optically awesome. I do worry about SDM failure. I suppose if it does fail, I will have it fixed, but probably not right away. Now that I have a K-30, focus peaking is an option and I can always manual focus. It's not like the lens becomes completely unusable. I do wish Pentax would move to a different AF option for the DA* lenses, though.

[calsan]

LensRentals.com - Lens Repair Data 2011

Newly released lenses tend to have higher repair rates. IS lenses have higher repair rates. Zooms have higher repair rates. Newly introduced IS zoom lenses would seem to a repair just waiting to happen. But then that’s why they give warranties.

[Tom S.]

LensRentals.com - Lens Repair Data 2011

Interesting link but there are a couple problems, especially since they don't have any Pentax lenses. Another issue is this is a lens rental service, and just like car rentals, I'm betting the lenses are subjected to more abuse by users. For example, the No. 1 failure rate of 40% was recorded for the Sigma 50-500mm lens, yet there has been very little complaints here from users to indicate a failure rate anywhere near that percentage. If one were to compare a lens like the Bigma, which received very little complaints here, yet was number one on the rental sites repair list, with a Pentax 60-250mm SDM which has received lots of complaints here, should one expect a failure rate in the rental world of 80 to 100%? That's speculation on my part, but it could be true.

[robbiec]

Stupid poll.
If you experience a failure, get it fixed, it is what a warranty is for. If you bought 2nd hand, well there are places now that will replace and or rebuild the SDM motors and you're down a couple of hundred dollars. Throwing toys out of prams and switching systems at a probable loss sounds really idiotic. I also wonder how many "I have experienced it, left Pentax" votes you will capture, surely if they left Pentax they won't be hanging around here.

[reeftool]

I have eliminated the potential of the failure, by not acquiring any SMD lenses.

To this point, that is what I have done also. I'm not saying I'll never buy one but so far I have steered clear of SDM lenses.

[normhead]

To this point, that is what I have done also. I'm not saying I'll never buy one but so far I have steered clear of SDM lenses.

Good plan... if you want to minimize risk SDM definitely looks riskier than the old screw drive.


On the other hand, I decided the DA*60-250 was my "must have" lens, based on months of agonizing. I love that quiet smooth operation to the point I sometimes leave screw lenses in the bag when they might have something to offer. I and many others decided the quality of the lens and smooth quiet operation, was worth the risk. From my perspective.. you're probably missing out. I am however planning to buy a Tamron 70-200 2.8 in part as a back-up. But then, in my business I should always have a back up in any case... one slip on a hiking trail at the wrong time and I could smash any of the equipment I own to smithereens. I'd love to be able to sell my K-x and K20D to fund a k-30. But time has taught me I need 3 working bodies.

But back to the SDM thing... before I bought it, I realized that someday it will probably fail. The same is true for the screw drive motors that make AF possible in screw drive lenses. The same is true of your shutter. The difference with AF lenses is you hope they will still be around with future camera bodies through the years. But my guess is, with this new Canon system with the stepper motors and the camera knowing where the lens is through a positioning system will mean next generation lenses we be enough better than SDM that my DA*60-250 will seems as unworthy as the Sigma 70-300 that made the purchase of my *ist seem like such a good thing. As a guy who had to learn enough about robotics to teach it, it kind of blows me away that everyone isn't using stepper motors for AF already.

Manual focus is for people with great eyesight. Up until I was 40 I saw at 20 feet what most people saw at 15, and I found manual focus a snap. Now at 60+ with bifocals... I love auto-focus.

[Pioneer]

Everything eventually fails, even the metal, manual, mechanical cameras. There are far more posts on this site and others about sending cameras or lenses out for CLAs then there are about lenses with SDM failures. So the eventual failure of an SDM lens is probably a certainty, the only question is when. If, like Norm, you really enjoy using your lens, you will probably have it fixed. I guess the real question here may be; will you get your $800 dollars worth out of that lens before it dies? And the answer to that question almost certainly depends more on you than the lens itself. I have one myself and I really enjoy working with it. If it does die I am pretty sure I will have it fixed. Besides, based on what I have been reading in this one thread alone, I doubt that most of you want to buy an SDM lens at all, so I can't sell it to you. Maybe Norm and I can trade them back and forth between each other.

I have read a bunch on this forum about SDM failures, but interestingly, I haven't read a lot about it on the other forums I participate in. I don't really know what the actual failure rate is, but I do suspect it is probably quite a bit lower than the traffic on this forum would lead you to believe. But that is a function of the internet culture. Small problems frequently get blown out of proportion by the few people participating in these forums. Since SDM was new technology for Pentax I can believe that a few examples probably did have some problems, and the bugs are probably still being worked out. Again, this seems to be a pretty prevalent fact in our society today. Electronic gadgets are often put on the market before the bugs have been cleared up because people have become so impatient to get their hands on the new stuff. Finally, when you look at how many of these lenses change hands on the auction sites and classified sections of these forums, I suspect that one person's problem often gets spread to several people before someone actually takes action to get it fixed. You have no idea how many times I have read someone say; "sell it and buy another one."

[Docrwm]

Everything eventually fails, even the metal, manual, mechanical cameras. There are far more posts on this site and others about sending cameras or lenses out for CLAs then there are about lenses with SDM failures. So the eventual failure of an SDM lens is probably a certainty, the only question is when. If, like Norm, you really enjoy using your lens, you will probably have it fixed. I guess the real question here may be; will you get your $800 dollars worth out of that lens before it dies? And the answer to that question almost certainly depends more on you than the lens itself. I have one myself and I really enjoy working with it. If it does die I am pretty sure I will have it fixed. Besides, based on what I have been reading in this one thread alone, I doubt that most of you want to buy an SDM lens at all, so I can't sell it to you. Maybe Norm and I can trade them back and forth between each other.

I have read a bunch on this forum about SDM failures, but interestingly, I haven't read a lot about it on the other forums I participate in. I don't really know what the actual failure rate is, but I do suspect it is probably quite a bit lower than the traffic on this forum would lead you to believe. But that is a function of the internet culture. Small problems frequently get blown out of proportion by the few people participating in these forums. Since SDM was new technology for Pentax I can believe that a few examples probably did have some problems, and the bugs are probably still being worked out. Again, this seems to be a pretty prevalent fact in our society today. Electronic gadgets are often put on the market before the bugs have been cleared up because people have become so impatient to get their hands on the new stuff. Finally, when you look at how many of these lenses change hands on the auction sites and classified sections of these forums, I suspect that one person's problem often gets spread to several people before someone actually takes action to get it fixed. You have no idea how many times I have read someone say; "sell it and buy another one."

We just went down this path in another thread. This one really is tilling the same soil. The Survey here on the PF forum is pretty conclusive that the DC motors have had 0 reported problems in all the lenses that they have been used in (1 total) and the SDMs have failure rates much higher (well anything off 0 is much higher) but several have fairly large n's reported with 1/3 reporting failures. Love the lenses all you want, but trying to make it out to be an internet issue or people only focusing on problems is just trying to hide a very real issue. Nearly 60 years of social psych research tells us one thing very clearly - the more someone pays for an item the more they value it regardless of the facts about the item. Same item presented to 2 groups - SAME ITEM - but with different prices for each group, the higher priced item gets rated dramatically higher in quality, etc. than the identical item at a lower price. So, what lenses are the highest priced in the Pentax pantheon? Might the SDMs be in the highest quartile? Hmmm........

- Done -

[normhead]

Same item presented to 2 groups - SAME ITEM - but with different prices for each group, the higher priced item gets rated dramatically higher in quality, etc. than the identical item at a lower price. So, what lenses are the highest priced in the Pentax pantheon? Might the SDMs be in the highest quartile? Hmmm.......

So, what your saying is I like my DA*60-250 because it costs more.

Faster focusing, quieter operation and sharp images have nothing to do with it? It's all that money I paid for it. So, you're saying if I paid $1600 for my Sigma 70-300 and $300 for the DA* 60-250 I'd think the Sigma was better?

That is quite the observation.

You're belief in your ability to apply general research to a specific individual astounds me. You do know that you can have 70% of men be smarter than 30% of women in a given area of study? You do know that in such a case it is still possible that a woman might be the absolute smartest of those tested. What I'm saying is, group statistics do not apply to individual cases?

So therefore claiming that anyone who prefers and SDM because they are more expensive, as if it was some kind of beer, where it's all opinion anyway, you do us all a disservice. It's incredible what lengths folks will go to, not to win an argument straight up, but to win it by discrediting their opponent.

Before I bought my SDM lens, I tried two other lenses, read the resolution charts and decided based on that what to buy. I did my best to avoid the high priced item, and get the best for what I do. So you can quote your studies all you want. But essentially, they don't tell you anything accept trends.

But hey, enough making fun of you....

The reason that study is irrelevant to the topic at hand is because the same item was sold to two different groups, which means no product comparison was involved. In the case of SDM lenses, almost all of us have screw drive lenses, almost all of us buying SDM lenses have other lenses to compare them too, and the odds are we have based our purchases on performance and by how much they outperform our current lenses. If the selection and value of lenses were based on price alone.. then what you say might be true.. people valuing what they own based on how much it cost might be true. But ultimately with lenses, for photographers like myself... in the end it's, how many keepers am I getting from each lens. What is the quality of those images? My perception based on price is quickly brought in to focus by IQ issues.

My DA* 60-250 doesn't beat every lens in it's focal length, we like the Tamron 90 better at 90mm. But it's very close, and very good even compared to a great prime. And it happens to be the most expensive lens I own.

Both of those statements can be true... without meaning I was influenced by it's price. Clearly if I was influenced by it's price, I wouldn't think so highly of the Tamron 90 macro which I got second hand for $275. There can be other things going on. And the longer you own a piece of equipment the less likely you are to be influenced by it's price. Many of the folks on here have had their SDM lenses for years. ANd as much as I love my Tamron 90, I'd never compare it's build quality to a DA*. You need to learn to give credit where credit is due.

[lytrytyr]

If the selection and value of lenses were based on price alone.. then what you say might be true.. people valuing what they own based on how much it cost might be true. But ultimately with lenses, for photographers like myself... in the end it's, how many keepers am I getting from each lens. What is the quality of those images? My perception based on price is quickly brought in to focus by IQ issues.

Perhaps some statistician could analyze the lens reviews on this forum,
to see if there's any correlation between the average price and the rating.

[Pioneer]

We just went down this path in another thread. This one really is tilling the same soil. The Survey here on the PF forum is pretty conclusive that the DC motors have had 0 reported problems in all the lenses that they have been used in (1 total) and the SDMs have failure rates much higher (well anything off 0 is much higher) but several have fairly large n's reported with 1/3 reporting failures. - Done -

Hmm. I guess since this was discussed in a separate thread then it obviously has to be "conclusive." But I still say that any survey conducted on this forum is really only polling the opinions of the members of this forum, and probably not all of them. However, since you insist that the previous thread concluded that the SDM failure rate is far too high, then it obviously must be so. No thread posted here can be biased in any way.

[Docrwm]

Hmm. I guess since this was discussed in a separate thread then it obviously has to be "conclusive." But I still say that any survey conducted on this forum is really only polling the opinions of the members of this forum, and probably not all of them. However, since you insist that the previous thread concluded that the SDM failure rate is far too high, then it obviously must be so. No thread posted here can be biased in any way.

Data and evidence seem to have little impact on many peoples love for Pentax, even the SDM lenses. It might be more convincing if your post wasn't just snide and actually included anything resembling information on the data that has been collected. The issues with samples and all the other dodges for discounting the data available have already been offered and addressed. This really is getting old. The SDMs fail, at a much higher rate then non-SDM lenses, period. Buy them if you like, people bought Pintos even after the evidence was clear they were unsafe. It's your money.

[normhead]

DId you just completely ignore my post?

What's getting really old is your refusal to admit to the advantages the build quality, the water resistance and superior optics of of the SDM lenses. Your Pinto argument could be made as well for people who like Mercedes. A buddy of mine who was the service manager of a Mercedes dealership once told me, you don't get out of an oil change for a Mercedes for less than $1500. If you can't afford it, don't buy one. That would be a more apt analogy. We pay for silent operation, faster AF, beautiful build quality and better IQ. There is nothing Pinto about it. Like the guy who buys the Mercedes... if you can't afford $300 or $400 for a repair every now and then, maybe you need the Tamron 70-200. Cheaper to buy. More reliable (if it makes it through the first year).But has a 10% return rate (according to forum reviews) , and average build quality. But let's be plain here.

For those of us interested in IQ, which is what DA* and SDM lenses are mostly about... we'll pay for the repairs if necessary. If we like the lens we'll put up with any speculative grief. Speculative because you say it's going to happen to me... because I own one, but you won't say when, will you?

Pinto schminto...