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10-04-2019, 04:19 PM   #1
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Possible focusing issues with k-3?

I had some weird issues out of the blue today (I thought everything worked fine yesterday, so it was frustrating me today to say the least)

So first issue: I was taking photos on a tripod using live view. exposure, time was like between 1-6 seconds, Stabilization was off, I was using focus highlighting. Used the timer so there was no movement. Only like 1 out of every 4 or 5 photos was in focus. I tried manual and auto focus, I tried live view and through viewfinder. I fiddled with micro adjustments for a long time. I could not figure out what was making it not be in focus. I thought maybe the lens was moving after I focused it? I was using the k3 with the 18-135. I have had the set for 5 years, never experienced such difficulty. I was thinking I was going crazy and it must be something simple. Live view had the areas highlighted, took a photo and nothing that was highlighted was in focus. The table was focused, but I went through every micro adjustment and it did not seem to make a difference. I was photographing jewelry setting on a table. The ones in focus turned out great.

So after getting frustrated, I just decided to take it off the tripod, switch lens to the 100mm macro and go outside. Nearly every photo was in a focus, but a few were missed which is unusual, for this lens, to me, but far more where in focus than the 18-135. However it would randomly just go way out of focus, like hunt and miss, but what would happen would it would "lock" it seemed. If I moved the camera and focused on something far away, it would just make the "whirring" sound like it was trying to focus but it wouldn't move. I would have to turn to manual focus, physically move the lens, turn it back to auto and then it would focus. In the end I just used manual focus. Which at least worked here - it did not work earlier on the 18-135 consistently. I had this lens for a few years now and never had it hunt for focus so much nor get stuck out of focus.

So is this a focusing issue with k-3? Or am I having just one of those moments that I forgot to do something simple? I find it hard to believe I have 2 lenses malfunctioning at the same time? (the 18-135 has taken a beating so I could believe that has issues, but it was fine yesterday using the tripod)

Anyone have insight?

10-04-2019, 04:31 PM   #2
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2 things I can think of: dirt on the sensor and change in the AF settings
10-04-2019, 04:53 PM   #3
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QuoteOriginally posted by sergysergy Quote
2 things I can think of: dirt on the sensor and change in the AF settings
Someone else suggested cleaning the lens contacts so I may try cleaning those and seeing if anything is on the sensor. Thanks!
10-05-2019, 02:54 AM   #4
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Sensor = af sensor, not the image sensor.

10-05-2019, 03:51 AM   #5
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The 18-135 has a tendency to drift, at least my unit will extend by its own weight, that's why I am using a rubber band to "make it solidary" to the focus ring, which offers a lot more resistance.

As for focusing, my hit rate goes down as soon as move from AF.S and Spot. I have found the K3 is very unforgiving and even with the 55-300 PLM I have misses if I'm using 9 points or AF.C.

Good luck!

10-05-2019, 08:13 AM   #6
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I recommend cleaning the autofocus sensor. I did have trouble for a while with focus on my K3II, however, after cleaning all was good.
10-05-2019, 09:31 AM   #7
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QuoteOriginally posted by bwgv001 Quote
I recommend cleaning the autofocus sensor. I did have trouble for a while with focus on my K3II, however, after cleaning all was good.
Just out of curiosity (and having a K3 as well ) how do you clean the AF sensor??

Last edited by Excalibor; 10-05-2019 at 09:32 AM. Reason: typos
10-05-2019, 08:57 PM   #8
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QuoteOriginally posted by bwgv001 Quote
I recommend cleaning the autofocus sensor. I did have trouble for a while with focus on my K3II, however, after cleaning all was good.
I actually do that often. It does make a difference, I think like mentioned above, It might have been lens creep. Because the 100mm lens I used after focused well, like every shot was in focus, it would just hunt and then not refocus.

---------- Post added 10-05-19 at 11:59 PM ----------

QuoteOriginally posted by Excalibor Quote
Just out of curiosity (and having a K3 as well ) how do you clean the AF sensor??
I put it on bulb mode and wipe the sensor, which is a little bump to the front and bottom of the lens opening. Bump being the technical term ;-)
Itís pointed out in the manual I believe

---------- Post added 10-06-19 at 12:05 AM ----------

QuoteOriginally posted by Excalibor Quote
The 18-135 has a tendency to drift, at least my unit will extend by its own weight, that's why I am using a rubber band to "make it solidary" to the focus ring, which offers a lot more resistance.

As for focusing, my hit rate goes down as soon as move from AF.S and Spot. I have found the K3 is very unforgiving and even with the 55-300 PLM I have misses if I'm using 9 points or AF.C.

Good luck!
I am thinking it was lens creep now. I noticed the longer 12 sec timer images were worse, so I think it might have been creeping down during the timer? I have never experienced that before so it did not occur to me, at the time. I will try a rubber band!

10-06-2019, 02:30 AM   #9
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QuoteOriginally posted by Murfy Quote
I actually do that often. It does make a difference, I think like mentioned above, It might have been lens creep. Because the 100mm lens I used after focused well, like every shot was in focus, it would just hunt and then not refocus.



---------- Post added 10-05-19 at 11:59 PM ----------







I put it on bulb mode and wipe the sensor, which is a little bump to the front and bottom of the lens opening. Bump being the technical term ;-)

Itís pointed out in the manual I believe

---------- Post added 10-06-19 at 12:05 AM ----------





I am thinking it was lens creep now. I noticed the longer 12 sec timer images were worse, so I think it might have been creeping down during the timer? I have never experienced that before so it did not occur to me, at the time. I will try a rubber band!
Good luck with that! Umm using the rubber band wrist ... erm, bands? from the Dr Who 50th Anniversary... If you gotta rubber, let's do it with style!

Thanks for explaining how to clean the AF sensor, my camera might thank some care... Cheers!

10-07-2019, 07:30 PM   #10
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QuoteOriginally posted by Murfy Quote
I had some weird issues out of the blue today (I thought everything worked fine yesterday, so it was frustrating me today to say the least)

So first issue: I was taking photos on a tripod using live view. exposure, time was like between 1-6 seconds, Stabilization was off, I was using focus highlighting. Used the timer so there was no movement. Only like 1 out of every 4 or 5 photos was in focus. I tried manual and auto focus, I tried live view and through viewfinder. I fiddled with micro adjustments for a long time. I could not figure out what was making it not be in focus. I thought maybe the lens was moving after I focused it? I was using the k3 with the 18-135. I have had the set for 5 years, never experienced such difficulty. I was thinking I was going crazy and it must be something simple. Live view had the areas highlighted, took a photo and nothing that was highlighted was in focus. The table was focused, but I went through every micro adjustment and it did not seem to make a difference. I was photographing jewelry setting on a table. The ones in focus turned out great.

So after getting frustrated, I just decided to take it off the tripod, switch lens to the 100mm macro and go outside. Nearly every photo was in a focus, but a few were missed which is unusual, for this lens, to me, but far more where in focus than the 18-135. However it would randomly just go way out of focus, like hunt and miss, but what would happen would it would "lock" it seemed. If I moved the camera and focused on something far away, it would just make the "whirring" sound like it was trying to focus but it wouldn't move. I would have to turn to manual focus, physically move the lens, turn it back to auto and then it would focus. In the end I just used manual focus. Which at least worked here - it did not work earlier on the 18-135 consistently. I had this lens for a few years now and never had it hunt for focus so much nor get stuck out of focus.

So is this a focusing issue with k-3? Or am I having just one of those moments that I forgot to do something simple? I find it hard to believe I have 2 lenses malfunctioning at the same time? (the 18-135 has taken a beating so I could believe that has issues, but it was fine yesterday using the tripod)

Anyone have insight?
I'm a bit confused here! Were you having focus problems in both live view and with phase detect AF? if you were having problems with both its probably not your AF sensor that is causing you problems although it probably won't hurt cleaning it. I suspect focus breathing instead.
10-08-2019, 08:29 PM   #11
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QuoteOriginally posted by Larrymc Quote
I'm a bit confused here! Were you having focus problems in both live view and with phase detect AF? if you were having problems with both its probably not your AF sensor that is causing you problems although it probably won't hurt cleaning it. I suspect focus breathing instead.
Yes it was both. It was lens creep. My 18-135 was sliding down after I focused it. I need a new lens-either replacing or getting another one. Itís pretty ďwell lovedĒ and I think it just started because I never noticed it before.

I think I just happened to have another separate issue with the 100mm but since I cleaned off the contacts everything seems fine with that lens.
10-21-2019, 07:50 PM   #12
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I too have the same problem, my K3 would be focusing just fine one minute and then out of the blue it will not lock focus and will beep like it has attained focus, I never thought to try it out on phase detect focusing. I did blow out the shutter box with a bulb blower and I even reset the entire camera to factory settings, it seemed to help, in fact over the weekend it only stopped focusing on me just one time.
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