50-135 SDM not working

There's a sort of user serial number database over at PF link
It may help a bit.

I know it's an old thread, but worth re-visiting I think. My 50-135 does need to be 'woken up' sometimes but I've also noticed a different issue which only happens when the lens is on my K-5iis, not on my K-3. Sometimes the shutter won't fire, it seems to be trying to go but doesn't make it. It's only a problem when the 50-135 is attached. I can resolve it by taking the battery out and putting it back in again. Any suggestions as to what this might be?

Regards
David

Is it a fully charged Pentax battery? Maybe the current is low, perhaps even a battery reaching the end of its life?

What is the life expectancy for a Pentax camera battery? I've never had to replace one yet despite the fact some of my cameras must, particularly the K5, one of the early ones, must have shot tens of thousands of images.
Maybe its time I invested in a couple of spares.
David

Typically something like 1000 charge cycles is the figure I normally see quoted. After that, there will be a point where it isn't performing properly, but I suppose that will vary to some degree.

Thanks all,
Appreciate the replies. I've been debating about getting rid of my Sigma Mk2 70-200mm and replacing it with a 50-135mm. Really miss not having WR in a telephoto and watching YouTube VLOG's I see a lot of landscape images now being taken with telephoto lenses, mainly Canon L series which are WR. The Sigma isn't WR so, as I'm so anal about my gear, it would never see the light of day if there even was a hint of rain in the air so it's not getting, or going to get, the use it should.

Saw a Sigma 70-200mm sell on eBay for just shy of £550, part ex isn't far off that either but what worries me is the SDM issues. For landscapes if the AF fails to kick in then not an issue as I'll switch to MF, but for studio portraits or taking it out to the town centre in the rain I can't be having a 'hang on a sec, any minute now, bear with me' moment so I'm really torn what to do.

I was hoping that by now they'd have been fixed with a repair that stops this happening but looking at that serial number list it would appear not :

Had my 50-135 for some time now. Had one moment when it seemed a bit lazy, but cleaned the contacts and gave it a run, and no problems since.

The problems with the 50-135 seemed to have been solved some time ago, but not publicised, as very few if any reports of SDM issues these days.

Be very wary of the serial number list. As I understand it Pentax do not use sequential serial numbers, so you can't tell when a lenses was manufactured.

The SDM is slow on this lenses, so unless your studio and town centre shots involved anyone or anything moving fast you may find mf is just as quick.

Your money I know, but I ignored the naysayers and have had plenty of time to enjoy my 50-135, which in terms of IQ is as good as the best.

Never had an issue with my 50-135 and a couple year old now, shame cannot say the same about my 17-70 second hand when I bought it but lets say it takes some wakening up.

Slightly off topic, but had SDM failure a few years ago on my DA* 16-50mm F2.8 ED AL [IF] SDM, changed it to screw drive and no problems.

Hi John, it's not a battery issue as it has happened with several different batteries in the camera. I always use fully charged batteries and on one particular day when doing a festival shoot I replaced the battery 3 times and it happened with all of them. After it happened and I re-inserted the same battery all was good again, so it can't have been battery power causing the problem.

Regards
David

Laugh at the idea of modifying the lens, which was purchased with "silent" operation in mind, to screw drive at risk of even more damage. Why not just buy a cheaper screwdrive lens in the first place. Note to self: Go and put your 16-50 on each camera and shoot a few images. Fingers crossed and buttocks clenched