DFA 100 Macro WR Autofocus Failure

**bigoak** · 09-15-2017, 06:19 AM

Hello,

Just had my 100 Macro be unable to autofocus on my K1. It was locking out at max magnification before, i come back a few weeks later and it will not autofocus at all. Any ideas why this might be happening?

AF works fine with all of my other (SDM) lenses.

Thanks

Basie · 09-15-2017, 06:38 AM

Hi bigoak Have you tired it on another camera body as well. There was quite a few reports of the SDM contacts on the lens base coming loose. They are the two innermost electrical contacts and are identical. Mine bent and could not make contact any more. I straightened it and it word well until it bent again and broke off. I am waiting for a new SDM contact module to have it working again

normhead · 09-15-2017, 06:41 AM

Originally posted by Basie

Hi bigoak Have you tired it on another camera body as well. There was quite a few reports of the SDM contacts on the lens base coming loose. They are the two innermost electrical contacts and are identical. Mine bent and could not make contact any more. I straightened it and it word well until it bent again and broke off. I am waiting for a new SDM contact module to have it working again

My DFA 100 Macro WR is screw drive..... there's an SDM version?

I'm guessing you need to send it in for repair.
I have dealt with the SDM contacts issue before on my DA*60-250, but in my experience if a screw drive lens stops working, it needs parts.
I guess it could be the screw drive mechanism in the camera though, if all your other lenses are SDM, I guess you wouldn't notice. Stick another screw drive lens on the camera to see if it works.

**Larrymc** · 09-15-2017, 09:39 AM

From what I can find the DFA 100 Macro is screw drive only. There are no SDM versions of the lens. Looks like you either have a screw drive lens problem or a screw drive camera problem.

If you have another screw drive lens give it a try to isolate the problem.

You might try reseating the lens to see if that might correct the problem (screw drive alignment).

Last edited by Larrymc; 09-15-2017 at 09:56 AM. Reason: addition

Unregistered User 8 · 09-15-2017, 05:39 PM

Originally posted by bigoak

Just had my 100 Macro be unable to autofocus on my K1

Can you hear the cameras screw drive motor trying to focus the lens? if not, then the motor is kaput. If the motor is working, then shaft driving the focus internally in the lens is probably the cause. Either way, your K-1 or lens may need a trip to hospital.

Good luck.

Basie · 09-17-2017, 01:15 AM

Originally posted by normhead

My DFA 100 Macro WR is screw drive..... there's an SDM version?

Oops. Now i know. I don't have a DFA 100 Macro 100mm ( yet ) and I answered the SDM story. Should have checked

Cheers

**bigoak** · 09-18-2017, 02:11 AM

Originally posted by pjv

Can you hear the cameras screw drive motor trying to focus the lens? if not, then the motor is kaput. If the motor is working, then shaft driving the focus internally in the lens is probably the cause. Either way, your K-1 or lens may need a trip to hospital.

Good luck.

Definitely hear the motor trying to work. This problem is most noticeable with subjects ~2m away while in live view. As the lens searches, it extends out to max magnification and the is supposed to retract to find focus. This extension is now accompanied by a higher pitched noise as it fails to retract.

Unregistered User 8 · 09-18-2017, 04:10 AM

Originally posted by bigoak

This extension is now accompanied by a higher pitched noise as it fails to retract.

That is a worry. Because your lens is able to drive one way but not the other, please visually check the end of the drive on the camera and lens for any distortion. While the lens is off the body, move the AF/MF switch and make sure that the drive shaft is extending fully when in the AF position, and retracting fully when in the MF position.
Again, good luck.

09-15-2017, 06:19 AM	#1
bigoak Site Supporter Join Date: Apr 2017 Location: Bayern Photos: Albums Posts: 186	DFA 100 Macro WR Autofocus Failure Hello, Just had my 100 Macro be unable to autofocus on my K1. It was locking out at max magnification before, i come back a few weeks later and it will not autofocus at all. Any ideas why this might be happening? AF works fine with all of my other (SDM) lenses. Thanks

09-15-2017, 06:41 AM	#3
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	Originally posted by Basie Hi bigoak Have you tired it on another camera body as well. There was quite a few reports of the SDM contacts on the lens base coming loose. They are the two innermost electrical contacts and are identical. Mine bent and could not make contact any more. I straightened it and it word well until it bent again and broke off. I am waiting for a new SDM contact module to have it working again My DFA 100 Macro WR is screw drive..... there's an SDM version? I'm guessing you need to send it in for repair. I have dealt with the SDM contacts issue before on my DA60-250, but in my experience if a screw drive lens stops working, it needs parts. I guess it could be the screw drive mechanism in the camera though, if all your other lenses are SDM, I guess you wouldn't notice. Stick another screw drive lens on the camera to see if it works. Last edited by normhead; 09-15-2017 at 06:49 AM.*

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09-15-2017, 06:38 AM	#2
Basie Pentaxian Join Date: Aug 2011 Location: Windhoek, Namibia Photos: Gallery Posts: 991	Hi bigoak Have you tired it on another camera body as well. There was quite a few reports of the SDM contacts on the lens base coming loose. They are the two innermost electrical contacts and are identical. Mine bent and could not make contact any more. I straightened it and it word well until it bent again and broke off. I am waiting for a new SDM contact module to have it working again

09-15-2017, 09:39 AM	#4
Larrymc Site Supporter Join Date: Jun 2014 Location: Mississippi, USA Posts: 5,252	From what I can find the DFA 100 Macro is screw drive only. There are no SDM versions of the lens. Looks like you either have a screw drive lens problem or a screw drive camera problem. If you have another screw drive lens give it a try to isolate the problem. You might try reseating the lens to see if that might correct the problem (screw drive alignment). Last edited by Larrymc; 09-15-2017 at 09:56 AM. Reason: addition

09-15-2017, 05:39 PM	#5
Unregistered User 8 Closed Account Join Date: Mar 2015 Photos: Gallery Posts: 8,694	Originally posted by bigoak Just had my 100 Macro be unable to autofocus on my K1 Can you hear the cameras screw drive motor trying to focus the lens? if not, then the motor is kaput. If the motor is working, then shaft driving the focus internally in the lens is probably the cause. Either way, your K-1 or lens may need a trip to hospital. Good luck.

09-17-2017, 01:15 AM	#6
Basie Pentaxian Join Date: Aug 2011 Location: Windhoek, Namibia Photos: Gallery Posts: 991	Originally posted by normhead My DFA 100 Macro WR is screw drive..... there's an SDM version? Oops. Now i know. I don't have a DFA 100 Macro 100mm ( yet ) and I answered the SDM story. Should have checked Cheers

09-18-2017, 02:11 AM	#7
bigoak Site Supporter Join Date: Apr 2017 Location: Bayern Photos: Albums Posts: 186 Original Poster	Originally posted by pjv Can you hear the cameras screw drive motor trying to focus the lens? if not, then the motor is kaput. If the motor is working, then shaft driving the focus internally in the lens is probably the cause. Either way, your K-1 or lens may need a trip to hospital. Good luck. Definitely hear the motor trying to work. This problem is most noticeable with subjects ~2m away while in live view. As the lens searches, it extends out to max magnification and the is supposed to retract to find focus. This extension is now accompanied by a higher pitched noise as it fails to retract.

09-18-2017, 04:10 AM	#8
Unregistered User 8 Closed Account Join Date: Mar 2015 Photos: Gallery Posts: 8,694	Originally posted by bigoak This extension is now accompanied by a higher pitched noise as it fails to retract. That is a worry. Because your lens is able to drive one way but not the other, please visually check the end of the drive on the camera and lens for any distortion. While the lens is off the body, move the AF/MF switch and make sure that the drive shaft is extending fully when in the AF position, and retracting fully when in the MF position. Again, good luck.