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09-11-2012, 03:21 PM   #31
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QuoteOriginally posted by Catalana Quote
So, was Pentax able to replace Tamrons' PZD design with its own SDM (meaning it was small enough to fit the space constraints), or have they just renamed the PZD to SDM. In the latter case, it would mean that Pentax is able to control "Standing Wave" technology at the interface of lens and body, but it is not at all clear if SDM uses "Traveling Wave" or "Standing Wave" principles. It could be, that either principle is independent of the signal received from the autofocus sensor or Pentax added a different interface chip to the lens, so that it could correctly interpret the focus data from the body. Quite ambiguous...
Own SDM, Pentax don't make SDM so how can they have their own SDM?
It could very well be that Pentax uses both types in different lenses, nobody says all SDM motors use by Pentax are the same.
Nikon goes even further by naming normal DC motors SWM (silent wave motors = ultrasonic motor), it's just branding.

09-11-2012, 03:27 PM   #32
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QuoteOriginally posted by Anvh Quote
Own SDM, Pentax don't make SDM so how can they have their own SDM?
It could very well be that Pentax uses both types in different lenses, nobody says all SDM motors use by Pentax are the same.
Nikon goes even further by naming normal DC motors SWM (silent wave motors = ultrasonic motor), it's just branding.
It is NOT just branding. As I have said, you can have two engineers who have the same, precisely the same, materials to work with to construct a widget to perform a function. Engineer A produces an efficient machine that is reliable and completed the task. Engineer B, remember he has the same tools and materials precisely, produces an inefficient and breakdown prone machine.

Then there is the issue of different grades of materials from the supplier. Two machines from the same engineer can be very different even though they use the same technology because the bean counters for project A buy Grade A widgets and for project B they buy Grade F widgets.

So, its not as simple as they "are the same." Not by a long shot.
09-11-2012, 03:33 PM   #33
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QuoteOriginally posted by Docrwm Quote
It is an interesting question. The problem for me is that Pentax has 2 silent motor technologies already, and use both currently. While the motors may well be the same, their implementation in the lens itself is different. We know this from BOTH Pentax's own statements about SDM and DC being different in their implementation and the fact that we have multiple, and embarrassingly frequent, failures of SDM in zooms and absolutely no reported failures of the DC design/technology. So, even if SDM, DC, and PZD are all the same technology (Standing or Traveling wave) the implementation via engineering and design is decidedly different. So, if its all the same (or they are really using the PZD motors and just relabeling them) why choose to say they are SDM and make a big deal out of it in their marketing?
DC design/technology has failures, just look at other brands

DC is also very different technology then SDM or PZD, the DC engine works with magnetism while SDM and PZD work by vibrating "legs" with alternating current which then move or turn a surface by friction.
So Pentax is correct by naming PZD to SDM and not DC if that is the case.
09-11-2012, 03:42 PM   #34
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QuoteOriginally posted by Docrwm Quote
It is NOT just branding. As I have said, you can have two engineers who have the same, precisely the same, materials to work with to construct a widget to perform a function. Engineer A produces an efficient machine that is reliable and completed the task. Engineer B, remember he has the same tools and materials precisely, produces an inefficient and breakdown prone machine.

Then there is the issue of different grades of materials from the supplier. Two machines from the same engineer can be very different even though they use the same technology because the bean counters for project A buy Grade A widgets and for project B they buy Grade F widgets.

So, its not as simple as they "are the same." Not by a long shot.
Well, Pentax, Nikon, Sony, Panasonic, Tokina, Tamron and Sigma (i might have missed a few) don't make ultrasonic engines only Canon and Olymopus make their own engines so that means the rest use a supplier for their engines.

Sure some products are better then other products I don't deny that but since the engines Pentax use arent made or even designed by themselves it's called branding and there is indeed a chance they are the same. I'm not saying they are the same just that they are both ultrasonic engines.

09-11-2012, 04:34 PM   #35
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Short of having an exploded view diagram and circuit diagram of the Pentax design, the only other option is to take them apart and reverse engineer them.
Any folks out there with a Pentax SDM lens being used as a door stopper?
09-11-2012, 04:38 PM   #36
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Does this help?
http://forum.xitek.com/thread-821417-1-1-1.html
09-11-2012, 04:45 PM   #37
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Did Pentax just license the lens formula, or are they just putting a different shell on Tamron lenses? Obviously whichever is the case, Pentax is going to name things by their own nomenclature.

The reality is that the SDM in the DA *55 is different from the one in the DA *50-135 and 16-50. Yet, they are named the same. Unless Pentax tells you the exact motor, it is impossible to know whether it is the same or different.
09-11-2012, 05:17 PM   #38
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QuoteOriginally posted by Rondec Quote
Did Pentax just license the lens formula, or are they just putting a different shell on Tamron lenses? Obviously whichever is the case, Pentax is going to name things by their own nomenclature.

The reality is that the SDM in the DA *55 is different from the one in the DA *50-135 and 16-50. Yet, they are named the same. Unless Pentax tells you the exact motor, it is impossible to know whether it is the same or different.
It's clear that it's not simply the motor that is the issue. Pentax has had a range of SDM lenses - some with very few problems, some with a lot of problems. The issue appears to be, based on a variety of factors and sources of information, a design fault with the zooms primarily. They got it right with the 18-135 but they called it "DC" instead and claimed that it was a cheaper product/design/materials - don't care, it works and is reliable - unlike the SDM. So, again, why call the motors in the 18-270 "SDM" if they're all the same per what some here seem to be chanting absent any actual knowledge? Why not avoid the baggage associated with "SDM" and just call it "DC"? Could it be that a specific set of design criteria are called "SDM" and this lens fits those criteria? Could it be that they think they have positioned "SDM" to command higher prices for essentially the same technology? Could it be that there really is a difference in "SDM" vs. "DC" and they were honestly describing the technology in the 18-270? The problem is that at this stage we have absolutely no way of knowing. So, will the 18-270 be plagued with failures like the other "SDM" zooms? Will it be as reliable as the 18-135 "DC" lens? Is it really a Tamron lens, with their silent motor technology, but with a Pentax shell and label slapped on it?

The World May Never Know!

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09-11-2012, 07:36 PM   #39
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It could be that Tamrom use SDM technology but call them PZD
09-11-2012, 07:48 PM   #40
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QuoteOriginally posted by bobmaxja Quote
It could be that Tamrom use SDM technology but call them PZD
Yes that is possible. Of course, their engineering/design of the materials could be worlds better than Pentax's failure at SDM too.
09-11-2012, 07:48 PM   #41
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QuoteOriginally posted by Anvh Quote
There is nothing original about Pentax SDM and Pentax don't make the ultrasonic motors either, it's like saying the sensor in the D7000 is made by Nikon while we all know it's from Sony, also Pentax won't officially say they use Sony sensor in the K5.
It's very likely that in the DA* lenses there are different ultrasonic motors and that the same motors are use by other brands as well, they are off the self products.

Same with the processor, the Prime II is just a Fujitsu Milbeaut that also Nikon use....


It's the same with Apple A4 processor in the iPhone 4, the chip is for the most part designed and fully manufactured by Samsung...


Could very well be that in one of the lenses their Ultrasonic Engine is used FUKOKU Co., Ltd. | Ultrasonic motor

Canon, Fukoku, Asmo, SII, Canon Precision, Shinsei, Kyocera, Olympus and Mitsuba or the ones in Japan making these motors.
I'm with Anvh on this one (although the A4 is at heart an ARM processor with additions by others, not just Samsung, so hardly their total design - drawing parallels is always fraught with peril, but in this case it underlines the point about using other people's components).

It would be instructive to see what the rates of recent failures on SDM drives are. As stated many times over, the drive motor is just a part of the drive system, which is what Pentax are claiming in the wording for the 18-270. The system includes the drive motor, the gearing and the drive electronics - which of these are Tamron's and which are Pentax's is anyone's guess.
09-11-2012, 07:52 PM   #42
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QuoteOriginally posted by Docrwm Quote
It's clear that it's not simply the motor that is the issue. Pentax has had a range of SDM lenses - some with very few problems, some with a lot of problems. The issue appears to be, based on a variety of factors and sources of information, a design fault with the zooms primarily. They got it right with the 18-135 but they called it "DC" instead and claimed that it was a cheaper product/design/materials - don't care, it works and is reliable - unlike the SDM. So, again, why call the motors in the 18-270 "SDM" if they're all the same per what some here seem to be chanting absent any actual knowledge? Why not avoid the baggage associated with "SDM" and just call it "DC"? Could it be that a specific set of design criteria are called "SDM" and this lens fits those criteria? Could it be that they think they have positioned "SDM" to command higher prices for essentially the same technology? Could it be that there really is a difference in "SDM" vs. "DC" and they were honestly describing the technology in the 18-270? The problem is that at this stage we have absolutely no way of knowing. So, will the 18-270 be plagued with failures like the other "SDM" zooms? Will it be as reliable as the 18-135 "DC" lens? Is it really a Tamron lens, with their silent motor technology, but with a Pentax shell and label slapped on it?

The World May Never Know!
I don't think it's a given that it isn't the motor that's the problem. As you say, the applications are all different, as a result of different loads and gearing. If they chose one drive motor for all these, then this may be at the heart of the issues. Like you say, though, we may never know.
09-11-2012, 09:19 PM   #43
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btw I wonder why we pentax shooters can not also buy Tamron 18-270...like it was case with DA18-250 there was also Tamron 18-250 to buy for K-mount. I also wonder if there was any real differences (i do not mean outlook&colors here) between DA18-250 and Tamron 18-250 cos somehow I do believe that DA18-270 do follow the path of DA18-250...if Pentax/Tamron 18-250 lenses were same then we have good reason to believe that also Pentax/Tamron 18-270 lenses are same now...only difference is that now we not have choise to buy Tamron labeled lens.So what was the point of DA18-270 and not let us get Tamron 18-270 long time ago already? I have no idea...
09-11-2012, 11:11 PM   #44
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QuoteOriginally posted by 123jippo Quote
btw I wonder why we pentax shooters can not also buy Tamron 18-270...like it was case with DA18-250 there was also Tamron 18-250 to buy for K-mount. I also wonder if there was any real differences (i do not mean outlook&colors here) between DA18-250 and Tamron 18-250 cos somehow I do believe that DA18-270 do follow the path of DA18-250...if Pentax/Tamron 18-250 lenses were same then we have good reason to believe that also Pentax/Tamron 18-270 lenses are same now...only difference is that now we not have choise to buy Tamron labeled lens.So what was the point of DA18-270 and not let us get Tamron 18-270 long time ago already? I have no idea...
IIRC, the main difference with the 18-250 variants was the addition of SMC to the Pentax edition.

It may have been that Pentax also demanded a tighter tolerancing on manufacturing, allowing for less variation between copies. This, of course, is what happens in a number of manufacturing situations, where a higher price is put on product that falls within tighter quality specifications.
09-12-2012, 12:33 AM   #45
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QuoteOriginally posted by RobA_Oz Quote
IIRC, the main difference with the 18-250 variants was the addition of SMC to the Pentax edition.

It may have been that Pentax also demanded a tighter tolerancing on manufacturing, allowing for less variation between copies. This, of course, is what happens in a number of manufacturing situations, where a higher price is put on product that falls within tighter quality specifications.
LOL, if that was the case, we'd have the "perfect system". From your statement above, you imply that Pentax has some form of quality control a step above Tamron's. Maybe two decades ago.., but Pentax's own SDM is so bad, they have to re-brand another technology as their own (tongue in cheek). Even then they are still unable to offer an equivalent warranty (6 years versus 1 year) . If their marketing department can spin the specs of their new flagship camera, I'll take a stab at their lenses. Shenanigans, as someone mentioned before, albeit for the "new" focusing system on the K-5II ..
Once you start to dissect or dissociate the lens lineup from the bodies, you start seeing a gradual decrease in effort to maintain complementary quality between the two. It has been like that for at least a decade.
How can Tamron maintain a 6 year warranty period versus Pentax's 1 year period for their purported "quality SDM" lenses. Then factor in the recent price increase, just so they can offer a 50% discount to arrive at previous MSRP's.
Ricoh, you have your work cut out for yourself. Let's just see how deep of a hole you want to dig, before you decide it's time to get your house in order. It makes me wonder just what you bought the K-mount for!
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