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**stemked** · 01-12-2017, 05:45 PM

Hi All.

My K3 has recently had some issues with locking on and letting me release the shutter with my 150-450 (I often have to switch to manual focus to release the shutter). The camera is about three years old and has been through some pretty rough times from high humidity in Costa Rica to very dusty times in Australia. I haven't updated the software on it either. Can I expect with the updated software and professional cleaning that I can expect improved focusing performance? If so where have you (in the US) been getting your K3's cleaned up, and about how much does that run?

Thanks!

Doug

**tduell** · 01-12-2017, 06:50 PM

Are you attempting to focus on a close item when the lens focus range limiter is set to (say) 6m=inf?
This may not be your problem, but it has caught me out a couple of time.

Cheers,
Terry

**stemked** · 01-12-2017, 08:05 PM

I don't think so, but its possible. I'll be more vigilant next time.

**BigMackCam** · 01-13-2017, 05:38 AM

It could be that the phase-detect AF sensor has dust or debris on it. The sensor is at the bottom of the mirror box. Lock the mirror up as if you were going to clean the sensor then, using a bulb-style blower pointed at the phase detect sensor, give it a few blasts of air. Even better if you hold the camera with the mount facing down, so gravity can work its magic on any dislodged dust / debris. Give it a try, it may resolve the problem.

audiobomber · 01-13-2017, 06:00 AM

The fault may not be with the camera. AF problems are commonly lens related. Does this happen with other lenses? Have you tried to AF Adjust the 150-450? Focus that is slightly off will prevent the camera from releasing the shutter.

I would definitely recommend a software upgrade, but I doubt that will resolve the focus issue you are having.

01-12-2017, 05:45 PM	#1
stemked Site Supporter Join Date: Feb 2009 Location: Indianapolis Photos: Gallery \| Albums Posts: 527	Focusing Issues K3. Hi All. My K3 has recently had some issues with locking on and letting me release the shutter with my 150-450 (I often have to switch to manual focus to release the shutter). The camera is about three years old and has been through some pretty rough times from high humidity in Costa Rica to very dusty times in Australia. I haven't updated the software on it either. Can I expect with the updated software and professional cleaning that I can expect improved focusing performance? If so where have you (in the US) been getting your K3's cleaned up, and about how much does that run? Thanks! Doug

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01-12-2017, 06:50 PM	#2
tduell Loyal Site Supporter Join Date: May 2015 Location: Melbourne Posts: 1,517	Are you attempting to focus on a close item when the lens focus range limiter is set to (say) 6m=inf? This may not be your problem, but it has caught me out a couple of time. Cheers, Terry

01-12-2017, 08:05 PM	#3
stemked Site Supporter Join Date: Feb 2009 Location: Indianapolis Photos: Gallery \| Albums Posts: 527 Original Poster	I don't think so, but its possible. I'll be more vigilant next time.

01-13-2017, 05:38 AM	#4
BigMackCam Digitiser of Film Join Date: Mar 2010 Location: North East of England Posts: 20,701	It could be that the phase-detect AF sensor has dust or debris on it. The sensor is at the bottom of the mirror box. Lock the mirror up as if you were going to clean the sensor then, using a bulb-style blower pointed at the phase detect sensor, give it a few blasts of air. Even better if you hold the camera with the mount facing down, so gravity can work its magic on any dislodged dust / debris. Give it a try, it may resolve the problem.

01-13-2017, 06:00 AM	#5
audiobomber Veteran Member Join Date: May 2008 Location: Sudbury, Ontario Photos: Albums Posts: 6,806	The fault may not be with the camera. AF problems are commonly lens related. Does this happen with other lenses? Have you tried to AF Adjust the 150-450? Focus that is slightly off will prevent the camera from releasing the shutter. I would definitely recommend a software upgrade, but I doubt that will resolve the focus issue you are having.

Focusing Issues K3.

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