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**DAKS** · 11-13-2013, 01:22 PM

I read on the "other" forum that someone said their K-3 would not AF with their DA*55 lens.
My K-3 won't AF with the DA*50-135 lens, although it does AF with the DA*16-50.
Anyone else having problems?
David

JinDesu · 11-13-2013, 01:38 PM

Do you have any other lenses (non SDM especially)?

repaap · 11-13-2013, 01:56 PM

My DA*55 focuses just fine with my K-3.

bobmaxja · 11-13-2013, 01:58 PM

Could it be that the contact are dirty?

**DAKS** · 11-13-2013, 02:11 PM

My non-SDM lenses all work fine.
the 50-135 was working great on my K-5 earlier this week.

David

JinDesu · 11-13-2013, 02:18 PM

Does it still work with the k-5 now? Can you try cleaning the contacts on both the lens and the camera?

**DAKS** · 11-13-2013, 02:30 PM

I no longer have the K-5; traded it in so I could get the K-3.
I bought it locally at a store, so I can go back and try it with different cameras.
I may be able to do that this weekend.

I'll try cleaning the contacts, but I doubt if that is the problem. Just too much of a coincidence.

Thanks,
David

Bob from Aus · 11-13-2013, 04:00 PM

Did an indoor photoshoot at the weekend with the K3, 50-135 and a pentax flash. Went perfectly. AF seems to work better with all the lenses I have used so far, the most dramatic and impressive has been 100mm macro WR. I'm ecstatic at its ability to AF in crap light with my sigma 500. So far the AF is a winner but I don't own equivalent Nikon to compare.

**DAKS** · 11-13-2013, 04:22 PM

the AF is amazing with all other lens. Quick AF in almost pitch black rooms.
I'll be taking the 50-135 back to a dealer. (I've had it for years, since it first came out.)
David

Bob from Aus · 11-13-2013, 05:23 PM

Originally posted by DAKS

he AF is amazing with all other lens. Quick AF in almost pitch black rooms. I'll be taking the 50-135 back to a dealer. (I've had it for years, since it first came out.) David

before you do
1. Play with the AF/MF switch on the lens
2. i think someone else suggested to clean the contacts - these are 2 contacts on the inside of the lens not on the ones near the bayonet mount.
3. Place the focus on infinity (My 60-250 has an issue when it focuses close up - it is like tooth is missing and works Ok when I manually focus on infinity)

alcstudios · 11-13-2013, 05:52 PM

I've had no issues with my K3 and 50-135.

**DAKS** · 11-13-2013, 05:58 PM

thanks,
seems like a problem with the lens.
I'll try cleaning the contacts, etc. first.

mario_tr · 06-20-2014, 08:16 PM

Report of my k-3 AF in low light condition: with my 50-135mm f2.8 Pentax lens phase AF is slow, contrast AF during live view is faster than phase, in some case phase AF does not complete. same with my 16-50mm f2.8 and my 17-70mm f4.

With my Sigma 30mm f1.4 (non hsm lens) the focus is faster and more precise in contast AF rather than phase AF. I tried correct phase by adjusting it but I can not get the same result two times each after other.

My result is that phase AF

FilipWessman · 10-25-2014, 04:20 AM

I bought a K-3 late in 2013, IE when the camera was new on the market. I have experienced a problem with the AF, which came after a while.

Sometimes the AF does not kick in. The solution has been to twist the focus ring on the lens so it gets more out of focus. This awaken the AF so it starts working again.
This situation occurs in an ongoing photo session and it come suddenly without warning. When it does happen, I can turn the camera in another direction and the AF works, but when I turn it into the direction where the problem showed up, the problem comes back. The turning-the-focus-wheel trick works every time.

As a side note, I did have a problem just recently where the AF stopped working 2 times after I re-mounted a lens. It turned out I got dirt on the contacts, so do try and keep those clean, it helps.

stevebrot · 10-25-2014, 05:22 AM

Originally posted by FilipWessman

The solution has been to twist the focus ring on the lens so it gets more out of focus. This awaken the AF so it starts working again.

Hmmm...Unless your lens has quick shift, that is a good way to damage the AF mechanism on lens and/or body.

My understanding is that you are not seeing any indication of AF operation at times. Do you have the green hexagon? Are you able to get the AF to work by pointing the camera at something very near or very far? Physically jogging the system should not wake up anything unless there is a physical problem somewhere.

What lenses?

Steve

11-13-2013, 01:22 PM	#1
DAKS Site Supporter Join Date: Jun 2008 Location: McLean, VA Photos: Gallery Posts: 97	K-3 auto focus problem I read on the "other" forum that someone said their K-3 would not AF with their DA55 lens. My K-3 won't AF with the DA50-135 lens, although it does AF with the DA*16-50. Anyone else having problems? David

10-25-2014, 04:20 AM	#14
FilipWessman New Member Join Date: Jan 2014 Posts: 13	Another K-3 AF problem I bought a K-3 late in 2013, IE when the camera was new on the market. I have experienced a problem with the AF, which came after a while. Sometimes the AF does not kick in. The solution has been to twist the focus ring on the lens so it gets more out of focus. This awaken the AF so it starts working again. This situation occurs in an ongoing photo session and it come suddenly without warning. When it does happen, I can turn the camera in another direction and the AF works, but when I turn it into the direction where the problem showed up, the problem comes back. The turning-the-focus-wheel trick works every time. As a side note, I did have a problem just recently where the AF stopped working 2 times after I re-mounted a lens. It turned out I got dirt on the contacts, so do try and keep those clean, it helps.

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11-13-2013, 01:38 PM	#2
JinDesu Veteran Member Join Date: Jun 2011 Location: New York City Photos: Gallery Posts: 5,638	Do you have any other lenses (non SDM especially)?

11-13-2013, 01:56 PM	#3
repaap Pentaxian Join Date: Oct 2010 Photos: Gallery \| Albums Posts: 6,242	My DA*55 focuses just fine with my K-3.

11-13-2013, 01:58 PM	#4
bobmaxja Veteran Member Join Date: Mar 2010 Location: Laval, Quebec Canada Posts: 2,171	Could it be that the contact are dirty?

11-13-2013, 02:11 PM	#5
DAKS Site Supporter Join Date: Jun 2008 Location: McLean, VA Photos: Gallery Posts: 97 Original Poster	My non-SDM lenses all work fine. the 50-135 was working great on my K-5 earlier this week. David

11-13-2013, 02:18 PM	#6
JinDesu Veteran Member Join Date: Jun 2011 Location: New York City Photos: Gallery Posts: 5,638	Does it still work with the k-5 now? Can you try cleaning the contacts on both the lens and the camera?

11-13-2013, 02:30 PM	#7
DAKS Site Supporter Join Date: Jun 2008 Location: McLean, VA Photos: Gallery Posts: 97 Original Poster	I no longer have the K-5; traded it in so I could get the K-3. I bought it locally at a store, so I can go back and try it with different cameras. I may be able to do that this weekend. I'll try cleaning the contacts, but I doubt if that is the problem. Just too much of a coincidence. Thanks, David

11-13-2013, 04:00 PM	#8
Bob from Aus Veteran Member Join Date: Jul 2011 Location: Australia Photos: Gallery Posts: 1,094	Did an indoor photoshoot at the weekend with the K3, 50-135 and a pentax flash. Went perfectly. AF seems to work better with all the lenses I have used so far, the most dramatic and impressive has been 100mm macro WR. I'm ecstatic at its ability to AF in crap light with my sigma 500. So far the AF is a winner but I don't own equivalent Nikon to compare.

11-13-2013, 04:22 PM	#9
DAKS Site Supporter Join Date: Jun 2008 Location: McLean, VA Photos: Gallery Posts: 97 Original Poster	the AF is amazing with all other lens. Quick AF in almost pitch black rooms. I'll be taking the 50-135 back to a dealer. (I've had it for years, since it first came out.) David

11-13-2013, 05:23 PM	#10
Bob from Aus Veteran Member Join Date: Jul 2011 Location: Australia Photos: Gallery Posts: 1,094	Originally posted by DAKS he AF is amazing with all other lens. Quick AF in almost pitch black rooms. I'll be taking the 50-135 back to a dealer. (I've had it for years, since it first came out.) David before you do 1. Play with the AF/MF switch on the lens 2. i think someone else suggested to clean the contacts - these are 2 contacts on the inside of the lens not on the ones near the bayonet mount. 3. Place the focus on infinity (My 60-250 has an issue when it focuses close up - it is like tooth is missing and works Ok when I manually focus on infinity)

11-13-2013, 05:52 PM	#11
alcstudios Senior Member Join Date: Sep 2011 Location: Texas Photos: Albums Posts: 146	I've had no issues with my K3 and 50-135.

11-13-2013, 05:58 PM	#12
DAKS Site Supporter Join Date: Jun 2008 Location: McLean, VA Photos: Gallery Posts: 97 Original Poster	thanks, seems like a problem with the lens. I'll try cleaning the contacts, etc. first.

06-20-2014, 08:16 PM	#13
mario_tr Inactive Account Join Date: Aug 2010 Location: Canada Photos: Gallery Posts: 9	Report of my k-3 AF in low light condition: with my 50-135mm f2.8 Pentax lens phase AF is slow, contrast AF during live view is faster than phase, in some case phase AF does not complete. same with my 16-50mm f2.8 and my 17-70mm f4. With my Sigma 30mm f1.4 (non hsm lens) the focus is faster and more precise in contast AF rather than phase AF. I tried correct phase by adjusting it but I can not get the same result two times each after other. My result is that phase AF

10-25-2014, 05:22 AM	#15
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by FilipWessman The solution has been to twist the focus ring on the lens so it gets more out of focus. This awaken the AF so it starts working again. Hmmm...Unless your lens has quick shift, that is a good way to damage the AF mechanism on lens and/or body. My understanding is that you are not seeing any indication of AF operation at times. Do you have the green hexagon? Are you able to get the AF to work by pointing the camera at something very near or very far? Physically jogging the system should not wake up anything unless there is a physical problem somewhere. What lenses? Steve

K-3 auto focus problem

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