[suraswami]

Hello,

I bought a used Pentax DA * 55 mm lens from usedphotopro.com about 5 months ago. Due to pandemic not much use for the lens or chasing kids for photos.

When I got the lens initially I tested the lens and everything was working fine. I was able to use the lens with my K-3 for couple of park and lake trips.

Today when I tried to use the lens, initially after you mount and turn on the camera auto focus would not work. Have to change to manual focus, focus manually then switch to Auto focus, after a few seconds the focus motor comes to life and then it works. I was using the lens with my K3 all day and it seems to work fine.

Is this sign of SDM failure?

The lens still have about a month of warranty left, should I check for repair/refund/replacement?

Don't want a great lens to die like this, rather use the money to get the reliable Pentax 70mm lens or a Sigma 50mm F1.4.

[tokyoscape]

From what I read, Yes, it is sounding like the beginning of it.
I have the same lens and it is still working well even after about 6-7 months of not using.
Hope it won't happen again for you. If so, try to get a replacement asap.

[UncleVanya]

My copy sits unused for months but always wakes up. I’d return it.

[Nakedgun]

Mine died, alas, and after warranty. Sold.

[simsburyphoto]

I had an original 16-50 SDM that started with those types of symptoms that ultimately needed its motor replaced. However, I have other SDM lens including the 50-135, DA 200, and *55 that if I don't use them for an extended period they are initially have problems with autofocus, but if I leave them mounted on the camera for a few minutes they come back to life and they have never progressed to total failure. I will say that older 16-50 lenses seem to have the worst reputation for SDM failure. Also, my 16-50 ultimately started making grinding noises prior to failure and none of my other lenses have ever done that.

[suraswami]

Image quality on the 55mm is great, don't want to miss by returning it and trying to find another good copy which eventually might have the same issue.

After 24 hours of separation, mounted the lens onto the K3, no issues with Auto focus. May be should wait for more than 24 hours?

[simsburyphoto]

If you keep it off for a few days and it still works normally, probably you are o.k. Just use every couple of months.

[UncleVanya]

I will say that older 16-50 lenses seem to have the worst reputation for SDM failure. Also, my 16-50 ultimately started making grinding noises prior to failure and none of my other lenses have ever done that.

I cover probably about as many 16-50 and 50-135 as each other. The 200 and 300 are rarer.

Of course the numbers may reflect ownership as much as anything.

[aslyfox]

if you take the gamble and do not return it within the warranty period

( I would recommend returning it within the warranty period )

here are possible options for folks who might be able to help with a repair

US
KEH.com (GA, Most current and vintage gear)
Eric Hendrickson (Vintage cameras, Current and vintage lenses)
Precision Camera (Authorized to perform warranty service, NC)
Advance Camera (Most current and vintage gear, Portland, OR)
General Camera Repair (LA, CA)
Garry's Camera Repair (IL, select film SLRs)
International Camera Repair (LA, CA)
Halcyon Cameras | Vintage Camera Restoration (Vintage film cameras, San Diego, CA)
Camera Repair Japan (Services Sigma lenses and more, Atlanta, GA)
Allied Camera (MN, manual film cameras)
Bill Rogers Camera (LV, NV, film-era cameras and lenses)
Phototronic (Topeka, KS, film and digital camera repair)
Lezot's Camera Center (VT, film SLRs / medium format)

Read more at: Pentax Repair Facilities (Wordwide listing) - Page 9 - PentaxForums.com

follow the link to find active links

I have used Phototronic here in Topeka

[suraswami]

Whole evening the lens worked fine, even in SoCal cold weather ha ha.

Not sure if it was one off, may be I will remove the lens and keep it for couple of days and then try to confirm the issue.

[tibbitts]

The only lens I have subject to frequent SDM failure is the 60-250. I only have that because there is really no close alterative that works properly on a K-5. As far as I know very similar functionality to the lens you have is available in other non-SDM lenses, so if you have the opportunity, I'd replace the lens with an alternative.

[UncleVanya]

The only lens I have subject to frequent SDM failure is the 60-250. I only have that because there is really no close alterative that works properly on a K-5. As far as I know very similar functionality to the lens you have is available in other non-SDM lenses, so if you have the opportunity, I'd replace the lens with an alternative.

I have only seen a couple of those 60-250’s fail. They are quite reliable.

As for the DA* 55, I’ve seen a few failures but most seem ok. The lens offers better optical performance than any other autofocus Pentax fast fifty except for the new DFA.

[Sandy Hancock]

My first DA*55 (bought new) had a dead SDM out of the box. Its replacement is still going strong eight years later. It's a great lens.

Get it repaired or replaced ASAP before your warranty runs out.

[photogem]

Your symptoms are typical for SDM failure and it will come back and get worse (usually)
I can almost guarantee that. It always starts like this.


If it is in an early state (as yours), then this great tutorial (German though) can help you to get the SDM motor moving again.
Use google translator, it is pretty straight forward.
The SDM motor of the DA*55/1,4 SDM and procedure is 99% identical to the *16-55/2,8 SDM.

But if you wait too long, you need to send it in or use the lens like an A-lens (which is still worth it).

[suraswami]

I let the lens sit alone for more than 10 days, I didn't use my K-3 either. Over the holidays K-50 got to work. Last night I tested the lens mounted on the K-3, it seems to focus fine.

May be I will take a chance and ride on my luck, if it dies will try photogem's suggestion.