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03-06-2010, 01:02 PM   #1
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Help requested for k7 AF and power issues

Hi:

I have had a new k7 for a week or two and really like how it functions, but have two problems.

I opened several dozen pictures of our oldest son at Little League and none of the photos were sharp. I chalked this up to taking pictures at wide option apertures and perhaps my lack of skill shooting my quick moving son at wide apertures.

Shot RAW+JPEG (default "Bright" setting)

I took some more static photos of my son and saw the same lack of sharpness.

I was at the "Y" today with my wife and children and found the same softness issues. I took pictures from 1.4 to 8.0, close-up (keeping the minimum focus distance) and far away, of my children swimming and of some signs on the wall that of course were not moving. All were soft--shooting RAW.

I then used the micro adjustment on the k7 for my DA*55 and my Sigma 30 1.4. For both lenses as I moved to about +10 things got sharp(er). +5 was sharper and +10 seemed even sharper.

I have a DA* 50-135 and DA*16-50 and will test the focus issue with these, but with the 55 and 30 doing the same thing it appears to be an AF issue with the K7.

Has anyone had a problem like this with a new K7?

I know I can play with the sharpness setting for the JPEG and the display of RAW images, but with both the 55 and 30 responding to the micro adjustment--that tells me it is a camera/lens issue, and it appears to be a camera issue.

Also, I left the power switch to on (3 min power-off setting) and 2 dyas later the battery was dead and it was a fully charged battery that I had taken about 120 photos with (no flash, no Live View, little LCD use). I imagine there is some minimal power draw while in sleep mode, but would it be that much?

Other than these two issues I love the k7 and would seek to replace it if I somehow got a bad copy.

Thanx so much in advance for your thoughts.

Gregg

03-06-2010, 02:40 PM   #2
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Hi again

Hi:

From some additional reading I did it appears this is not an uncommon issue with the k7 and many have suggested simply returning for a new camera.

Has anyone else had this problem and was it fixable, was a debug possible/useful, or did you just return the camera?

Thanx again.

Gregg
03-06-2010, 02:56 PM   #3
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Seems like an faulty body. Send it back!
03-06-2010, 03:35 PM   #4
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If the 2 zooms need that sort of adjustment as well then I would return it.

03-06-2010, 03:43 PM   #5
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Hi

Thank you both for your responses.

I wanted to add that I am using firmware 1.03. I updated right when I receivd the camera so I do not know what pcitures with firmware 1.00 would have looked like, but it would make no sense that an upgrade would cause this.

Anyway, very dissapointed. I have a k20, which is great, but this sort of thing is frustrating. I know people can sometimes be quick to assume camera error rather than operator error, but I do not think I have done anything to cause this and have tried to remedy it. With the micro adjustment helping, but not completely fixing things, I think I am right on identifying the problem.

Oh well, I will play around with the k7 tonight for a bit, but I think it goes back to Amazon tomorrow.

Gregg
03-06-2010, 03:44 PM   #6
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invest in a focus chart or build one yourself. A single picture of that will answer all your questions about what is sharp and what is not. My K-7 and my Canon 1DmkIII both have needed a lot of adjustment with most of their lenses. It is not something that is unique to Pentax. On Pentax my 43mm had to be adjusted as far as the camera would allow but in the end it was perfect. My 16-50 did not have to be adjusted at all. On my Canon system my 70-200 F2.8 had to be adjusted +15 to get sharp.

So you may have a problem body or you may just have not done a good job of setting it up yet. I always test new gear at home on a focus chart before I waste time taking the camera out of the house to take fuzzy pictures.

With the battery issue I would recommend testing that too. I get 700 pictures from a battery (500 from my after-market battery) whether the camera has been on "sleep" for a week or not
03-06-2010, 08:17 PM   #7
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On its way back

Hi:

Thanx for the comment and suggestion. I tried all of my lenses and all are approximately equally soft at the default micro adjustment of 0 and get sharper at +10, but still do not achieve full sharpness like on my k20d. This ocurrs at apertures from 1.4 to 8.

I did not use a focus chart, but did some fairly intensive testing at home and also looked at all of my "real world" shots.

So, it is all packaged and ready to ship back to Amazon--which is replacing it with a new camera set to arrive on Tuesday.

Gregg
03-06-2010, 08:35 PM   #8
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QuoteOriginally posted by lawjbm Quote
Hi:

Thanx for the comment and suggestion. I tried all of my lenses and all are approximately equally soft at the default micro adjustment of 0 and get sharper at +10, but still do not achieve full sharpness like on my k20d. This ocurrs at apertures from 1.4 to 8.

I did not use a focus chart, but did some fairly intensive testing at home and also looked at all of my "real world" shots.

So, it is all packaged and ready to ship back to Amazon--which is replacing it with a new camera set to arrive on Tuesday.

Gregg
Real world is not what you should be interested in if you're trying to calibrate your lenses. You need to take a picture of some small text that is at a 45 degree angle to your camera - then focus on 1 line of that text and see if it is sharper in front of behind that line. If all your lenses are out by the same amount you can also adjust the focus for the body and then independently micro adjust each lens. All of this testing should be done at the widest aperture on each lens. It sounds like the new body is already on the way so don't be surprised if it appears to have the same issues

03-06-2010, 10:06 PM   #9
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Thanks for the comments

Hi:

Thanx so much for the comments. I appreciate your viewpoint. I do think, though, I put the camera through its paces.

And the test/chart vs. real world is an ongoing one. Some say using a test chart can result in "not seeing the forest for the trees." Just taking real world shots, however, does not allow for a strict review of the (usually) lens or camera.

I tested all four of my lenses (DA* 55, 16-50, and 50-135, and my Sigma 30 1.4). After seeing my shots of my children playing and swimming all looking uniformly soft and then all uniformly sharper as I used the micro adjustment to the max (but not sharp like with my k20d), I took a number of controlled shots of my wife and of objects on a table utilizing the micro adjustment in the k7. All lenses responded virtually identically. Shots were done from f1.4 to f8.

Anyway, having used the camera not knowing there was a problem (I had taken pictures of my oldest son at Little league over the course of a few days without uploading them) and then using the camera under more controlled conditions and getting the results I did I feel confident operator error is not at issue.

I will update, though, when I get the new k7.

Thanx again. I do appreciate your candor.

Gregg
03-07-2010, 05:27 AM   #10
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I think you misunderstand the debate regarding "tests vs real world". Some people will take pictures of brick walls and blue sky and other things to determine how much "edge sharpness" or vignetting a lens will produce when the reality is that those issues may not matter in 99% of photographs. What you are talking about here is "calibrating" your equipment which can ONLY be done with test charts. It would be like trying to play a song on a guitar without tuning it first. The only way to make the guitar work properly is to play each individual string and compare it to a tuning fork or electronic tuning instrument. Only AFTER you have tuned the guitar will it play good music.

To "tune" your k-7 you ONLY need to test the lens at its widest aperture and if you don't use a test chart then you are just guessing at what is in focus. There is no need to take it to F8. If all your lenses are out by the same amount (which you will be able to determine if you have taken pictures of a test chart) you can adjust the focus on the whole body to the max before adjusting each lens.

Good luck with your new camera.
03-07-2010, 12:20 PM   #11
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Hi

Kunik:

I understand your point and basically agree with what you explain for calibrating.

My problem is that all of my lenses equally are out of focus at the default setting and equally in better focus, but still not sharp--not even close, at the greatest micro adjustment. Since none of the lenses can come into focus on any calibration setting (positive or negative) I can conclude that the camera must be at fault. I tried every calibration setting.

As well, the battery/power issue tells me that I probably am right regarding a defective body.

Thank you again for your help.

Gregg
03-07-2010, 12:29 PM   #12
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Allegedly the AF performs poorly when the battery power is low. Perhaps, with your curious power (or lack of) issue, this kept the AF in a poorly performing state, which might have led to soft images - that's about all I can think of. But it's tentative at best. I'd say you've done the right thing.
03-07-2010, 12:59 PM   #13
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QuoteOriginally posted by lawjbm Quote
Kunik:

I understand your point and basically agree with what you explain for calibrating.

My problem is that all of my lenses equally are out of focus at the default setting and equally in better focus, but still not sharp--not even close, at the greatest micro adjustment. Since none of the lenses can come into focus on any calibration setting (positive or negative) I can conclude that the camera must be at fault. I tried every calibration setting.

As well, the battery/power issue tells me that I probably am right regarding a defective body.

Thank you again for your help.

Gregg
The power issue alone would be enough for me to return the camera. Even my aftermarket batteries are good for more than 700 shots. OF course, I'm not doing any video in there or doing a lot of in camera playing around with the photos. I have the screen basically shut off (press info button until it turns off).

I don't think I saw it in any of the posts but have you tried Manual focus? Can you get a Sharp shot at ALL?

WRT to the adjustments, someone mentioned calibrating for the entire body and Then for the lens. I don't think the 2 are additive. That is, each lens has it's own calibration regardless of the body (apply all) AF calibration. So, you cannot go more than +/- 10 either way.

03-07-2010, 10:45 PM   #14
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My experience with multiple Pentax Bodies from K10 to K7:
I need to do some AF adjustments to get pin point focus accuracy. Thanks to the hack to enable focus adjustment, I can easily do that to any camera body.

Yes, K7 or K20 has the ability to fine tune AF per lens, but if I hit -10 or +10 and the AF is still not spot on, I got no where to go except sending it back to service or replace for a new one.

Thats when I will perform the "service hack" and adjust the sensor directly. Obviously I need to know what are the typical adjustment for all my lenses. If I need at least +8 and above for all my lens, I will move the sensor back -5 so that I can still fine tune AF per lens accurately.

I'm too lazy to wait for camera service, so the service hack works well for me.
03-07-2010, 10:55 PM   #15
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I just invested in a lens align lite and its definitely worth the money:
LensAlign® Focus Calibration System

my sigma 70-200 f2.8 needed -6
sigma 30mm f1.4 needed -2
Pentax 16-50 F2.8SDM needed +4
etc.

It takes a while but its worth it.

I have one issue with the pentax k7 as the sigma 70-200 II and the Sigma 18-250 do not have any Lens EXIF data listed in the photo and the camera thinks they are the same lens.

So if you but the lens align make sure each lens you use is identified correctly.

Last edited by volvomanny; 03-07-2010 at 10:57 PM. Reason: spelling
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