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06-03-2014, 11:45 AM   #1
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Worsened AF performance.

I've earlier written about odd misfocusing, but can't find the threads - back then it would occur here and there and the it was very mind puzzling, because there was no apparent cause for the missed focuses.

My camera (K-30) has become much much worse - Simply put I don't trust it at all. My keeper rate has decreased severely because of this and while photographing, I've become a nerve wreck.

I just completed a bunch of events and ended up with a total of almost 13000 exposures, shot over a span of 5 days. Though I was quiet certain about the AF problem before these, I'm not fully convinsed something is wrong. It doesn't matter in what environment or light condition I photograph in and the camera also tends to front focus while it is rare, I miss by focusing past someone.

I'm not suffering from front focus issue in the typical sense. It can focus properly but the camera tends to front focus a lot and using different lenses such as Sigma 10-20mm, Sigma, 17-50mm, Pentax 35mm Macro, Sigma 70-200mm and more.

Is there anything I can do on my own or is there no way around sending it in for a checkup? I have other gigs and can't really sit tight for 4-6 weeks for the camera to return.

06-03-2014, 12:11 PM - 1 Like   #2
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If it is on multiple lenses, and erratic in nature, I think your only option is to send it in for adjustment.

You could try focus adjustment, but I think you already know that. Does k-30 have only one setting for fine tuning or multiple like k-5? Not sure.

How many exposures have you taken total? It just might be time for calibration & adjustment. If it was me I would pick up a used k-30 or k-50 as a backup, then send this one in for repair. After it gets back you could keep the second body as backup or sell it on, likely at little total cost. If these are paying gigs I would not be without a second body anyway, but that's just me.
06-03-2014, 12:23 PM   #3
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Thanks for your input. I can fine adjust individually, but it's not an option as the FF isn't constant - when the FF occurs, the amount can be different as well.

I currently own 2 K-30 bodies and having to miss one would still be hard, especial because, as you mention, it's a good thing to have a backup.

This particular camera body is ironically my backup camera and it has 23,894 exposure behind it. The main body has shot more than 3 times as many exposures, is way way more frequently used and on daily basis as well, and I'm not sensing the same problem on that one.
06-03-2014, 12:35 PM   #4
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One thing I got used to doing on my k-5 was focus twice. By that I mean focus as normal and after the focus locked, let go the focus button and press it again. This seemed to 'fine tune' the focus since in most cases it was close but maybe off a bit. Sometimes the second focus would not cause any change, sometimes enough to matter.

Since getting the k-5 back from repair at CRIS I do not seem to have as much trouble with it being off as I used to. But then I don't use it nearly as much since the k-3 is my main camera now. And I have never seen the erratic focusing on the k-3 like I did on the k-5.

Just food for thought, double focusing is not a solution just maybe a work around or something to test.

06-03-2014, 01:18 PM   #5
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Trust me when I say I do it all the time - I started doing it already when I first bought K-x and with lots of experience from studieshooting as well, I know what kind of differences it can make. Sometimes I also force the camera to re-focus at a completely different distance and then back to the subject, because the refocusing-but-no-change is no guarantee the focus is in fact optimal, even for group shots.
06-03-2014, 02:08 PM   #6
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QuoteOriginally posted by Zafar Iqbal Quote
Is there anything I can do on my own or is there no way around sending it in for a checkup? I have other gigs and can't really sit tight for 4-6 weeks for the camera to return.
Zafar, tough spot for sure, but it sounds like you can't trust the gear you're trying to earn money with. If it were me, I'd send it in and rent gear do do your gigs with in the mean time. It sounds like you are an experienced shooter so if all of a sudden, things are not working, it's probably a real issue and not something you are doing by mistake.
06-03-2014, 02:10 PM   #7
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QuoteOriginally posted by Zafar Iqbal Quote
Thanks for your input. I can fine adjust individually, but it's not an option as the FF isn't constant - when the FF occurs, the amount can be different as well.

I currently own 2 K-30 bodies and having to miss one would still be hard, especial because, as you mention, it's a good thing to have a backup.

This particular camera body is ironically my backup camera and it has 23,894 exposure behind it. The main body has shot more than 3 times as many exposures, is way way more frequently used and on daily basis as well, and I'm not sensing the same problem on that one.
If you have enough data to show that it's a problem on one body and not the other, it certainly points toward this not being anything related to "you" but rather to a needed adjustment in the offending K-30.
06-03-2014, 02:18 PM   #8
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I don't know if you let the camera select the focus point. The camera tends to pick what's closest if you let it determine what to focus on. It's safest to focus with the center point only and then recompose, or manually select the focus point (but that would slow you down).

06-03-2014, 03:17 PM   #9
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It's hard to reproduce the issue because it's not a fixed thing. Sometimes I can focus, shoot, refocus shoot etc. many many times and it's as if the AF won't comply at all. Other times it just nails the shots on first try.

I can't with 100% confidence say the problem only exists on one camera body alone because I typically use one body for wide to normal focals and the other for normal to long focals. I do get wrong focus shots with the other body as well, but not as often and not as severely. For instance, I can go wide at something like 20mm using f8 or so and still clearly be out of focus. By clearly I mean it's not a matter of camera shake as small bookeh clearly can be seen on faces.

QuoteOriginally posted by Ole Quote
I don't know if you let the camera select the focus point. The camera tends to pick what's closest if you let it determine what to focus on. It's safest to focus with the center point only and then recompose, or manually select the focus point (but that would slow you down).
I've never let the camera select the focus points. I mostly use the center point but there are also plenty of times where I manually select a focusing point. Currently I mostly use the center point because I had hoped it would lead to better accuracy.

I had hoped for a "oh, just do this and that and you'll be all set" solution, but I think the best thing to do, is to turn the camera in. I'll swap camera roles before doing o to see, if I get same issues using the other body.
06-04-2014, 03:12 AM   #10
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Have you tried resetting?
06-04-2014, 11:41 AM   #11
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I haven't. I suppose it won't hurt to try.

Last edited by Zafar Iqbal; 06-04-2014 at 11:51 AM.
06-04-2014, 02:13 PM   #12
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QuoteOriginally posted by Zafar Iqbal Quote
I haven't. I suppose it won't hurt to try.
Try cleaning the contacts on your camera and lens. And yes, resetting the camera is good, too.
06-04-2014, 02:15 PM   #13
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QuoteOriginally posted by Zafar Iqbal Quote
I haven't. I suppose it won't hurt to try.
Try cleaning the contacts on your camera and lens. And yes, resetting the camera is good, too.
06-04-2014, 05:08 PM   #14
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I reset the cam (and reconfigured it) and also cleaned the contacts on both the body and the lens.

I mentioned earlier it's hard to reproduce the issue. I also mentioned it's as if sometimes the AF won't comply at all.

I did some shots last night, where I took some photos of the monitor screen - though they weren't all tack sharp, they were good enough and better than the kind of issue I'm experiencing. If I had shown those to here, someone might have said: I don't see any real problem.

I just tried again now and the results are (drumroll) suddenly completely different. The other body behaved better, but it does fluctuate quiet a bit as well. I repeated the test using this forum as target, which was the case yesterday as well, to see if the forum colors might have an effect but the results were still very bad.

I must admit one thing: Last year I had some really bad experiences with sending in a camera for repairs (multiple reasons), and I now have trust issues with service centers. And since the body seemingly behaves randomly, I fear they will dismiss there is a problem instead of testing thoroughly, costing me both money and additional time for sending it back in again. Are there any kind of tests you guys can suggest, that should nail the fact, that I do have a problem?

Btw. You can see the 16 shots from today here: First 8 are from the problematic body, while the remainder 8 are from my other body. both using same lens, Sigma 17-50mm @ f2.8 1/100 (or so).

2014.06.05 - zafariqbal
06-05-2014, 12:47 AM   #15
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I just discovered this week that my K-5 does something similar with my DA*16-50. From 16-20mm it will front focus consistently.
I work around this by zooming in a bit, focusing and zooming out to wide angle again before shooting. I've got the AF button configured
for "cancel AF" so I can "AF lock" by holding that button.


Just a suggestion if you're looking for workarounds. It only works with zoom lenses of course.


Regards,
--Anders.
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