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View Poll Results: Select the option that best describes your agreement with the statement
I have a dual SDM and screw drive lens and I want the ability to choose the focus mechanism. 20258.38%
I am planning on buying a SDM/screw drive lens and I want the ability to choose the focus mechanism. 6919.94%
I will not buy a SDM lens until I have the ability to choose the focus mechanism. 7521.68%
Voters: 346. You may not vote on this poll

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06-11-2009, 05:05 AM   #31
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QuoteOriginally posted by Russell-Evans Quote
I can't be the only one that wants to use a TC with SDM lenses? I would imagine as more people buy the 200mm or 300mm, now that the SDM TC is off the lens road map, that they might entertain the idea as well? Especially as the old TCs that do seems to support SDM, are getting harder to find?

Why wouldn't you want to have the ability to switch?

Thank you
Russell
That has nothing to do with the poll. I agree, we should have a teleconverter that will work with the SDM lenses, but that isn't what the poll asks. Besides, while this flawed poll may suit your purpose (whatever that may be) it serves no other usefulness. Pentax/Hoya will not make any business decision based upon a poll with a small handful of responses, especially a poll that doesn't allow users to select the option that they are satisfied with the lenses as they are currently made.

06-11-2009, 05:08 AM   #32
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Unfortunately this is a red herring of a poll as it leaves out any option to leave SDM as it is.

Issues of SDM failure seem to happen with early batches of the DA* lenses, this from anecdotal evidence when talking to the Pentax repair tech where I am. No doubt I'm sure Pentax is aware of the issue and like any manufacturing company worth it's salt, improvements would have been made in subsequent production runs. After all, it costs money, time and goodwill to continue to render service for any defective SDM units, so it a no-brainer to make improvements in subsequent batches of lenses.
06-11-2009, 05:50 AM   #33
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QuoteOriginally posted by alohadave Quote
Why would you buy an SDM lens and disable SDM?

The SDM lenses that have screwdrives are transitional. As bodies progress, the screw drives are going to go away and all new lenses will be SDM.
Why switch from SDM to screwdrive? Well, unlike the OP (I guess) I have not had SDM fail on me, but:

-I'd like to use teleconverters that have screwdrive shaft but no SDM contacts because Pentax have not released a SDM converter
-I'd like to keep on using screwdrive converters even if Pentax release the 1.4x SDM converter because screwdrive AF will work with slower lenses and for converters including 1.7x and 2.0x, while 1.4x appears to be just below the limit for what works with SDM.
-I'd like to use macro tubes with screwdrive AF.
-I'd like to run my SDM lenses on screwdrive AF on the K-7 because it's been reported that while the SDM focus is marginally improved on the K-7, the screwdrive focus has gone balistic.
06-11-2009, 06:50 AM   #34
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I chose the third option even though I may not be buying any SDM/HSM lenses in the near term, or ever. Other than sound and an attempt to justify higher costs all anecdotal evidence here and on DPR say there is no difference in focusing speed.

Hmm, pay more money, get no options, get no performance benefits, but it runs quieter. I don't know what is holding me back from swapping all my lenses!

06-11-2009, 07:09 AM   #35
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let's look from the other side of the fence!

Please note This posting is to be a devil's advocate in the discussion, and no, I don't work for pentax.

while we are all discussing here what we want, how about looking at this issue from the other side of the fence.

shaft driven AF assemblies are high precision high labor intensive (for assembly), expensive things. SDM without mechanical drive offers a means of reducing the assembly cost significantly, and also takes a great big motor out of the camera body, making bodies lighter and cheaper as well.

In fact, many ultra low cost canikon bodies can only use shaftless SDM lenses, and it is only pro bodies that offer screw drive as well. These are the same bodies that also offer metering for non A lenses etc.

So, what we are discussing here is really wamting all of the features possible that others offer in a pro body, in a cost competitive to real amature bodies aimed at attracting the P&S market to DSLRs.

somewhere something has to give, or is this really where we draw the line and have a real "pro" body that offers 100% functionality across the entire pentax lens spectrum, including apature coupling (non crippled K mount) selectable screw drive or HSM drive, power zoom functions (I thought image size tracking was actuallly worth while), along with both TTL and P-TTL flash (user selectable) , .........
06-11-2009, 11:54 AM   #36
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QuoteOriginally posted by Tom S. Quote
I think you are overly optimistic if you think you'll get 50 people who are interested, let alone 50,000.

Well we have 50, only 49.950 to go.

Thank you
Russell
06-11-2009, 11:57 AM   #37
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QuoteOriginally posted by Rondec Quote
I don't understand why you would pay extra for SDM and then not use it.
It is pretty simple, because there isn't a SDM TC on the market and there isn't one on the road map.

Thank you
Russell
06-11-2009, 12:02 PM   #38
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QuoteOriginally posted by Lowell Goudge Quote
something to remember in all of this is that there are 2 varients of SDM (or what ever it gets called)

while it is true that some SDM lenses offer a mechanical drive down to the camera body, and hence offer two potential focusing systems, more advanced WSDM lenses DO NOT by limiting SDM technology to the first generation, which would offer both SDM and screw drive you are limiting the abilities of lens designers to some extent.

It's all up to you, but there may come a time when you want something that is only SDM compatible due to image quality.
Nobody is limiting the designers. No one is asking for more dual drive lens to be produced. All this poll is about is allowing the choice to use the screw drive or SDM on the lenses that have dual drive capability.

Thank you
Russell

06-11-2009, 12:27 PM   #39
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QuoteOriginally posted by Tom S. Quote
That has nothing to do with the poll.
It has everything to do with the poll.


QuoteOriginally posted by Tom S. Quote
I agree, we should have a teleconverter that will work with the SDM lenses, but that isn't what the poll asks.
We don't have a SDM TC, there have been a number of screw driven TC made that do work, it is pretty simple to make the connection that if we had the ability to chose between screw driven and SDM, we could use any screw driven TC.


Where's that marketing spiel, "Its about backward compatibility"? Why don't teleconverters count? Why is it that it is you can use the DA * 300mm on a istD, ist DS, ist DL, K100D, or K110D with a TC, but can't on the latest and greatest?



QuoteOriginally posted by Tom S. Quote
Besides, while this flawed poll may suit your purpose (whatever that may be) it serves no other usefulness.

Pentax/Hoya will not make any business decision based upon a poll with a small handful of responses, especially a poll that doesn't allow users to select the option that they are satisfied with the lenses as they are currently made.
But you aren't satisfied, you want to use your lens with a TC and there isn't one to be had. It also appears there will be none manufactured by Pentax as it has been removed frorm the road map. How can you be satisfied? How can anyone be satisfied?

Thank you
Russell

Last edited by Russell-Evans; 06-11-2009 at 04:45 PM.
06-11-2009, 12:40 PM   #40
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QuoteOriginally posted by Lowell Goudge Quote
So, what we are discussing here is really wanting all of the features possible that others offer in a pro body, in a cost competitive to real amature bodies aimed at attracting the P&S market to DSLRs.
No, what we are discussing here it simply enabling something that is already present. There is not added cost to the cameras, or to the lenses. The cameras and lenses under discussion already are built with SDM and screw drive capabilities. It is only software programing that prevents the use.

Thank you
Russell
06-11-2009, 12:55 PM   #41
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QuoteOriginally posted by Douglas_of_Sweden Quote
Why switch from SDM to screwdrive? Well, unlike the OP (I guess) I have not had SDM fail on me, but:

-I'd like to use teleconverters that have screwdrive shaft but no SDM contacts because Pentax have not released a SDM converter
-I'd like to keep on using screwdrive converters even if Pentax release the 1.4x SDM converter because screwdrive AF will work with slower lenses and for converters including 1.7x and 2.0x, while 1.4x appears to be just below the limit for what works with SDM.
-I'd like to use macro tubes with screwdrive AF.
-I'd like to run my SDM lenses on screwdrive AF on the K-7 because it's been reported that while the SDM focus is marginally improved on the K-7, the screwdrive focus has gone ballistic.
I haven't had the SDM fail. The only reason I put being able to switch to screw drive when SDM fails as a reason someone might want the option to switch to screw drive on SDM lenses is because there have been a number of posts noting that SDM has failed for different people through no fault of their own. I am also worried about the future when my one and only one SDM lens will be out of warranty.

I have to agree with you on your reasons for wanting the option although I have never used extension tubes, so I wasn't considering them.

Thank you
Russell
06-11-2009, 01:04 PM   #42
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QuoteOriginally posted by WheresWaldo Quote
Hmm, pay more money, get no options, get no performance benefits, but it runs quieter. I don't know what is holding me back from swapping all my lenses!
Well, the lenses are pretty nice performers and dual SDM screw drive lenses are the only WR lenses for Pentax until the WR dual kit lenses hit the market. I think used FA versions of the 200mm and 300mm are more expensive than the DA * 200mm and DA * 300mm as well.

The 17-70mm isn't a dual drive lens, so it pretty much is out of this discussion, but I can see your point if you were thinking about this lens when you posted.

Thank you
Russell
06-11-2009, 01:05 PM   #43
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SDM and Teleconverters

QuoteQuote:
Russell Evans
We don't have a SDM TC, there have been a number of screw driven TC made that do work, it is pretty simple to make the connection that if we had the ability to chose between screw driven and SDM, we could use any screw driven TC.


Where that marketing spiel, "Its about backward compatibility"? Why don't teleconverters count? Why is it that it is you can use the DA * 300mm on a istD, ist DS, ist DL, K100D, or K110D with a TC, but can't on the latest and greatest?


It is odd that there are no currently produced TCs that work with SDM. Oddly enough at least two older TCs do work. I have a "Tamron-F 1.4X Teleconverter for Pentax ZAF" and it works very nicely with the DA*300mm provided there is reasonably good light. One of the older Kenko TCs also works but not the current models. There appears to be a gap in the market for a new SDM compatible TC. Judging by the silly prices the Tamron 1.4 commands on ebay there should be a profitable opening for the third party providers.

Archie
06-11-2009, 01:21 PM   #44
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QuoteOriginally posted by creampuff Quote
Unfortunately this is a red herring of a poll as it leaves out any option to leave SDM as it is.
The poll isn't about changing SDM in any way. It isn't even discussing if SDM needs to be changed. It simply is about allowing the option to not use it.

QuoteOriginally posted by creampuff Quote
Issues of SDM failure seem to happen with early batches of the DA* lenses, this from anecdotal evidence when talking to the Pentax repair tech where I am. No doubt I'm sure Pentax is aware of the issue and like any manufacturing company worth it's salt, improvements would have been made in subsequent production runs. After all, it costs money, time and goodwill to continue to render service for any defective SDM units, so it a no-brainer to make improvements in subsequent batches of lenses.
It's nice to know they have improved the lenses, but what about the poor guy that has his SDM fail after the warranty period because he bought an early version? I don't see Pentax recalling the early batches of lenses. I don't see Pentax offering an extended warranty period for the serial numbers affected. Could they at least give the chance to use the lens by offering an option to switch to screw drive? Is that really asking too much?

How do you resolve the TC issue into a no-brainer?

Thank you
Russell

Last edited by Russell-Evans; 06-11-2009 at 01:36 PM.
06-11-2009, 01:34 PM   #45
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QuoteOriginally posted by Rondec Quote
I don't understand why you would pay extra for SDM and then not use it. If you just want a body driven lens, wouldn't you buy one? I guess I would just like to see them come out with a more durable, more potent version of SDM that wasn't as prone to motor burn out. The transition lenses with SDM and body driven options really are a lousy idea that probably significantly increases risk of lens failure.
You want more potent, so I'm assuming you think the SDM is slower than screw driven? If so, wouldn't it be nice to choose SDM for when quiet is needed, and screw driven when speed is needed?

I agree that Pentax can do whatever they want to improve future lenses, and I hope they do, but for the lenses that are on the market and are dual drive, there are more reasons to offer an option to be able to switch between SDM and screw driven, than there are arguments against.

Thank you
Russell

Last edited by Russell-Evans; 08-10-2009 at 09:42 PM.
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