SDM Strikes Again

I bought my DA*16-50 back in 2011. Its optics are excellent but the autofocus started to become unreliable around 18 months ago and just before Christmas it packed up altogether. Johnsons advised that a repair would be in the region of £180 to £220. Having read of others having multiple failures that didn't seem a good option to me. I'd read of software hacks to get the lens to revert to screwdriver mode but that required a Windows computer (I have a Mac) and my K3II wouldn't allow access to the necessary options in debug mode. So, what to do? Happily, I came across a hack that I could use with my Mac and so I decided to buy an older body, a K5II to reprogram the lens. The work took 3 minutes and now the lens is back in business, albeit a little noisier than before. I'll probably keep the K5II as a second body - maybe I'll need it again if/when my DA*50-135 packs up. I'm pretty pleased with this outcome but not so pleased with Pentax, who appear to have a head-in-the-sand attitude to this well documented problem. I've been using Pentax cameras for over 40 years and feel that I've shown them more loyalty than I've received from them. Why they can't get their dealers to offer this solution for a nominal cost - or for free? Anyway, I'm up and running again and looking forward to putting the lens to good use as the winter steam railway galas get underway.

I had to follow exactly the same route - it is frustrating that the fix to revert to screw drive is not offered as a nominal fee fix by Pentax. On the upside though I did sell my K5ii body for a small profit

I'm not sure it's a case of Pentax having their 'heads in the sand', it's more to do with the fact that the SDM Motors have a fundamental design flaw and it's not easy or possible for Pentax to re-engineer the internals of the lenses to rid them of this issue. To cure it would mean replacing the internal motor design with one which works on a different basis.

There were reports that Pentax had fixed the problem in later versions of these motors, but to be frank that's absolute rubbish, the later ones seem to fail just as much as the earlier ones did. There are exceptions to the rule, the SDM motors in the DA*300 don't seem prone to fail, I'm not sure why this would be the case.

It's such a shame because in all other respects the DA*16-50 and the DA*50-135 are great lenses.

Regards
David

I think you missed

There's a very simple answer to that question, i.e. the dealers make little or no margin from Pentax so they won't pay for it and Pentax as a manufacturer can't afford to give free warranty repairs on items that are not in the warranty period. The SDM issue is annoying and I think we all agree that Pentax could / should have done more a few years ago, but it's so well documented that I think most buyers of these lenses know what they're getting into when they buy them. There are millions of examples of mechanical / electrical items having design faults that cause things to fail outside of warranty periods and the manufacturers don't pay for repairs. If you go onto any BMW owners forum you will find hundreds of examples of BMW building items into their cars which are prone to fail prematurely, but BMW don't pay them.

Regards
David

I read Darrel's "this solution" in his question to refer to hacking the lens from SDM to screw-drive. His "3 minutes" of work. Excluding the time to locate and to purchase an older camera body.

I'm not an engineer but could it be to do with the DA*300 being a fixed focal length rather than a zoom? I should imagine the motor would be put under more strain
on a zoom lens.

The primes seem to be more reliable but they can fail. My DA*200 is currently in for SDM replacement.

A 50-135mm and a 55/1.4 both recently came up for sale recently in my area, which is rare as Pentax is not a common brand at all here in Spain. I'd love either of them as the optics are reputed to be excellent, but I'm just not willing to pay what's still a considerable price for lenses I know are prone to failure, even if there are work-arounds for some of them.

Pentax desperately need to release mark II versions of these lenses with the problem fixed, but that's been true for the entire time I've been a Pentax user (ten years in May) and there's no sign of it happening.

Designs are over 10 years old and from when Pentax was still an independent company, two changes of ownership and I guess Ricoh don't want to know about failures they are not originally involved with. Pentax is now only a small entity within a much larger parent. Frustrating that there has never been a recall, but as has been mentioned newer motors do fail (and Asahi Camera (Pramath) tells me he has had to reject batches quite recently).

I have 3 lenses with DA* SDM - the 16-50 is on it's 3rd motor (most recently done at Brentford Radio = Asahi Camera), the 60-250 on its' second and the 300 (I bought SH off here still on its' original.

I love my DA* lenses - when SDM is on song they're great.

Pentax aren't the only brand with technical issues, my Nikkor 80-400 has had to go to Nikon for a focussing failure (£330) and the 200-500 has zooming failure (well documented).

I believe updates might be forthcoming, depends on whether the K-3 line spawns a new model this year. If not I can see the DA* line disappearing.

Hi All - thanks for taking the time to reply to my post - all very interesting! Ideally, Pentax would have redesigned and retro-fitted free of charge via a recall. Back in the real world, that was never going to happen but by ignoring the issue Pentax haven't done themselves any favours. What I'd like to see is for Pentax to acknowledge that there is a problem and to "legitimise" the reversion to screwdriver mode for those of us that do not want to carry on with SDM. Whilst they were at it, they could also reinstate the full suit of options in the K3II and future camera's debug menu. I wonder why dealers won't carry out the software fix. Given that they are in place, we are only talking about a very small marginal cost. It would probably take longer to open the returned packaged body than to do the work itself! That said, I would have happily have paid £30 or so, although maybe not now I know how simple the fix is to implement, unless you only have a K3II. Best regards, Darrel

[quote:3496ace15f="ilovesaabs"].... Frustrating that there has never been a recall, but as has been mentioned newer motors do fail (and Asahi Camera (Pramath) tells me he has had to reject batches quite recently).

I have 3 lenses with DA* SDM - the 16-50 is on it's 3rd motor (most recently done at Brentford Radio = Asahi Camera), the 60-250 on its' second and the 300 (I bought SH off here still on its' original. [quote/]
Pramath is good - when they fitted a white solenoid to my K-30, he delayed handover until he was sure everything was OK, as it has since been.

Pramath is a great guy, you can spend ages talking with him. Fixed my FA*28-70 most recently, that lens is so good it's the one thing stopping me getting the D-FA 24-70 (and it confuses the hell in the Canon community:mrgreen

I had a sleepy sdm on my da16-50 which needed carefully waking up after whitch it worked fine.

My da300 and 60-250 have always been fine. (60-250 soon going up for sale)

As far as Pentax offering a free or cheap repair, try asking Apple to give your 10 year old iPhone a service !

Many thanks to a fellow member on PUF who lives a few miles from me my DA*16-50mm lens is now working again after being converted to screw drive. It seemed a complicated process needing computer skills that were beyond me but it only took him a few minutes because of his expertise. The lens has always been optically superb.
David