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10-29-2012, 05:27 AM   #1
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Did all K-r users have FF or BF AF problems ?

Did all K-r users have FF or BF AF problems ? did the k-r have af fine adjustment option ?

10-29-2012, 05:52 AM   #2
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It does have the AF fine adjustment option. Can't answer the first one.
10-29-2012, 06:13 AM   #3
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When I had my K-r, I did not experience any ff or bf problems and at that time I had more than 10 AF lenses.
10-29-2012, 08:10 AM   #4
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I too have several AF lens for my K-r. After a couple tests I decided I had a minor FF problem - follow these steps USING A TRIPOD...
#1- make sure your viewfinder's diopter adjustment is correct for your vision situation. Manually focus as best you can at a subject at infinity, then tweak your viewfinder using the little lever above the viewfinder for the sharpest image.
#2- Use auto-focus and compare how the AF functions show the viewfinder and liveview images. At infinity, there shouldn't be any difference (other than the reduced resolution of the LCD itself) ... If there is, we may be talking about a repair issue, not a simple FF or BF issue.
#3- Use auto-focus on an object just further than your close focus limit and repeat the steps in #2. No real difference?, no FF/BF. Small difference? Then you may need to use the built-in AF adjustment.

If you do need to make an adjustment, don't guess. Use a tool to accurately make your adjustments. You can buy the expensive tool or see THIS THREAD. It takes longer to read the instructions than it does to actually make any needed adjustment.

For what it is worth, I set my 18-55 kit lens at the mid-point in its zoom range to make my adjustments. It was worked just fine across all my AF lens. Especially as I rarely shoot wide-open.

10-29-2012, 08:24 AM   #5
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I had to send mine in. I had to adjust some lenses all the way to -10. I first noticed it with a fast lens, the FA50/1.4. My K100D didn't have any focus issues and the K-r did. I found that the adjustment was too extreme, and gave me no leeway, so I sent it to CRIS. If you are talking about the FF in tungsten lighting, if you set your white balance to tungsten then it will fix that particular issue.
10-29-2012, 09:53 AM   #6
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I have a K-r and don't have front/back focus issues. Though I still mess up focus sometimes. I think a lot of people just blamed the camera for their own mistakes, though.
10-29-2012, 10:15 AM   #7
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I think Pentax's focus mechanism is good, but I find that Auto-5 and Auto-11 selects the wrong focus point way too many times; especially when the image has lots of conflicting lines for the camera to choose from. For example, I get a sharp image of the branch the bird is sitting on rather than the bird's eyes and beak. It's easy to think this is a front or back focus issue.

I moved to Spot focus using only the center patch. Better but not perfect. I am now trying Select focus and rather than recomposing, using the 4-way controller, move to a different focus point.
10-29-2012, 10:24 AM   #8
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Honestly, I've had my k-r for about 18 months and taken about 5000 shots. I am by far not a pro.. Still learning the ins and outs of photography. I haven't tested it for FF or BF..

QuoteOriginally posted by Na Horuk Quote
I have a K-r and don't have front/back focus issues. Though I still mess up focus sometimes. I think a lot of people just blamed the camera for their own mistakes, though.
^This is my exact assumption. I feel as if I need to be more familiar with camera as a photog before blaming the camera for something I'm doing wrong.

10-29-2012, 08:27 PM   #9
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I bought a K-r from a forum member for my brother, and couldn't get it to auto-focus wrong at all.
10-29-2012, 09:00 PM   #10
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My K-r has problems with one lens in low light - the Tamron 17-50 f/2.8. It doesn't appear to be a bad copy of the lens, because it works fine on other bodies, and the K-r works fine with other lenses. Switching from AF.C to AF.S (contnuous to single-shot) solved the problem. Just something about my lens and body makes continuous mode guess wrong. I think the reputation far exceeds the actual problem (not saying no one had problems).
10-30-2012, 01:09 AM   #11
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The thing is, anyone that has a problem is more likely to post it online than someone who has no problem. And then people who read the reviews get frightened or use it to bash the brand.
10-30-2012, 03:11 PM   #12
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I have a K-r and have to set the focus adjustment all the way to -10. It would really need -11 to be exactly in focus if that were available but at -10 it is near enough for most situations.

It is the same with all the lenses I have except the Tamron 10-24mm. That one I need to set to between -8 and some -11 or -12 (if it existed) depending on the focal length. The other lenses are Sigma 150-500, Tamron 18-250, Tamron 90mm macro, Pentax 18-135 WR.

The same -10 adjustment is also valid for the manual focus lenses I have (to do AF confirm), including an 800mm f8 cat lens (actually I was surprised the AF sensor even worked at all at F8).

I have more recently got a K-30 and these same lenses all focus perfectly with the focus adjustment at zero. The 10-24 being again the exception but only needing -1 to +1 adjustment.


The AF on the K-r once went totally out such that I estimate it would have needed -20 or more adjustment. I thought maybe the AF sensor had got dirty - there was a good reason for suspecting that as there were tiny insects crawling around inside the camera. After blasting away with a rocket blower all over the mirror box to no avail (I had no idea where the AF sensor is located) I decided to do that which should never be done - I blasted it out with an air compressor at 6 bar. Somehow the K-r survived the ordeal and the AF is again working properly (though still with the -10 adjustment). Not sure what I was thinking at the time but perhaps I thought it was more likely to survive that than sending it overseas for repair.
11-05-2012, 04:20 PM   #13
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My K-r mostly focuses fine, although I generally check each lens individually for any front- or back-focus issues. My only lenses that have been dead-on no adjustment needed are my F 70-210/4-5.6 and DA 35/2.4. My Tamron 17-50 needs -5, and my FA 35/2, FA 50/1.4 and F 135/2.8 all need -1.
11-06-2012, 09:56 PM   #14
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I use a K-r and it does FF in tungsten light. The focus adjustment is not per lens as in the K-5 and newer bodies.

I may be wrong but I think the general consensus was that the AF module (SAFOX IX) design was flawed to begin with. I think this is caused by CA on the AF sensor when under tungsten light. The K-5 uses the same AF module but it has an additional light source sensor to compensate for this. The the K-30 went even further by adding (or improving) a lens in front of the AF sensor.

I'm not a camera technical expert, just basing on information I read from the internet. So anyone please correct me if I'm wrong.

I've done some AF comparison with my old DS in case you are interested. First test I did here.
11-09-2012, 11:43 AM   #15
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I had a K-r and had no problems with it...great camera!
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