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12-23-2009, 09:51 PM   #31
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QuoteOriginally posted by jacksonpritt Quote
Based on your attached images it looks like your camera is front-focusing when using your kit lens. If you look at her sweater, the texture of the sweater that is somewhat closer to the camera than her face looks nice and sharp, but her face is slightly out of focus.

I suggest sending the camera & lens back to Pentax and requesting that they be calibrated.
on the last picture, I think you're right. maybe the OP can do a few more tests and look across the image if the are portions that are sharper than the one portion that he is focusing on. maybe he could check out the previous images as well? anyway, the washed-out images makes it a bit difficult to see where the focus really is.

12-25-2009, 01:55 PM   #32
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QuoteOriginally posted by moSIN Quote
To be honest, I'm a little dumb struck by that. How much leeway (in inches) does the camera have when it beeps confirming focus lock?
You misunderstood. It's not a question of inaccuracy - it's a simple matter of the focus "point" not being a "point" at all, but rather a largish rectangle (about the size of the innermost bracket etched into the viewfinder). The camera can legitimately choose to focus on anything within that rectangle. You might put the focus point directly on someone's eye, but if their nose is within range of that rectangle, the camera is just as likely to focus there instead. Or, if part of the background is rwithin range, it might focus there instead - even if the background is *miles* behind the subject. Most of the time, the camera will tend to do what you want, but you can't automatically assume it will read you midn and focus exactly on the point you wanted - it can only be relied upon to focus *somewhere* within the range of the focus "point".

QuoteQuote:
Is there any specific technique that would help me get the focus where I want it to be or at least to improve my chances?
Just be aware of when there is something else within range of that center focus point, and try to aim the camera when focusing at a place where there is unlikely to be a problem. And after camera focuses, actually check the viewfinder to see if it focused where you wanted it to. If it didn't, it's usually quickest to simple override it manually, but you could simply try again and hoe the AF system will pick differently.

This is basically an issue with *all* AF systems - film and digital, P&S and DSLR. But you notice the problem far more often with a DSLR because DOF is so much shallower than with a P&S, and you can pixel peep and see problems you wouldn't have noticed with film.
12-28-2009, 01:32 AM   #33
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QuoteOriginally posted by moSIN Quote
Having played with the new K-x for a few days now, I still can't get rid of the feeling that maybe I didn't make the right choice?

In addition, I see a few threads here that report IQ issues in low ISO (softness and low contrast primarily). Is it a function of the kit lens? I can confirm that my kit 18-55 lens is rather soft at all apertures and somewhat lacking in contrast.
The kit zoom will be low contrast and soft compared to better lenses, but I don't think this is the real cause of the problem.

I'm just amused (in the wry sense, not ha ha funny sense) to find these "the K-x images don't meet my expectations" posts after I came to the same conclusion (after some intensely frustrating tests) and sold my K-x a few weeks back.

Basically I saw what you saw, even though I was typically using the FA limited lenses. There some oddities with the K-x image processing / sensor that produce objectively good but subjectively soft and flat images. Exactly what those are is hard to pin down. In my view:

- the blacks tend to never be truly black, and get less black as the ISO goes up.
- the images are sharp but not sharp, and the sharpness falls as the ISO goes up.
- there is quite a bit of pixel noise even at ISO200. Using the dynamic range extender at ISO400 has a lot of shadow noise when seen at 100%.
- there is none of the blochiness at high ISO typical of just about every other sensor I have seen. Instead the image just loses detail. The chroma noise reduction must be something intense...
- there may be some issues with the SR not being primed in some cases, so "sharpness" especially at low shutter speeds must be approached with care.
- there is a color cast, slightly pink or violet, to the images, but I didn't find this a bad thing, rather more true than the yellow, slightly dark tint to most of the dSLRs I have used.

Oddly enough I haven't regretted getting rid of my K-x. Now I've trained myself to see the peculiar "flaws" I can actually pick them out of even the dpreview samples. I like the K-x images less and less the more I see of them.

Overly processed. Flat. Unrealistic.

I went back to my K10D ...and lived happily ever after.
12-29-2009, 05:34 AM   #34
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QuoteOriginally posted by rjm Quote
The kit zoom will be low contrast and soft compared to better lenses, but I don't think this is the real cause of the problem.

I'm just amused (in the wry sense, not ha ha funny sense) to find these "the K-x images don't meet my expectations" posts after I came to the same conclusion (after some intensely frustrating tests) and sold my K-x a few weeks back.

Basically I saw what you saw, even though I was typically using the FA limited lenses. There some oddities with the K-x image processing / sensor that produce objectively good but subjectively soft and flat images. Exactly what those are is hard to pin down. In my view:

- the blacks tend to never be truly black, and get less black as the ISO goes up.
- the images are sharp but not sharp, and the sharpness falls as the ISO goes up.
- there is quite a bit of pixel noise even at ISO200. Using the dynamic range extender at ISO400 has a lot of shadow noise when seen at 100%.
- there is none of the blochiness at high ISO typical of just about every other sensor I have seen. Instead the image just loses detail. The chroma noise reduction must be something intense...
- there may be some issues with the SR not being primed in some cases, so "sharpness" especially at low shutter speeds must be approached with care.
- there is a color cast, slightly pink or violet, to the images, but I didn't find this a bad thing, rather more true than the yellow, slightly dark tint to most of the dSLRs I have used.

Oddly enough I haven't regretted getting rid of my K-x. Now I've trained myself to see the peculiar "flaws" I can actually pick them out of even the dpreview samples. I like the K-x images less and less the more I see of them.

Overly processed. Flat. Unrealistic.

I went back to my K10D ...and lived happily ever after.
i am surprised that any one expects the Kx to be all things and produce spot on images for enlargement. It is essentially a P&S camera with lens interchangeability.
I bet that Pentax target market for the Ks is the non critical end of the market and that is why the higher spec K20 and K7 are made. Pentax have those two for the professional and semi pro end of the market who want super sharp from their crops.
Using the 18-55 kit lens with my k10 on any subject the centre focused part of the image is always sharper than using the same lens on the same subject on my wife's Km.
Alistair

12-29-2009, 09:04 AM   #35
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It looks like digital sharpening and maybe some contrast enhancement being applied to the Oly image...how do Kx images look if you turn up the in camera sharpening, saturation, and contrast? I haven't used a Kx but does it also have bright/neutral options?

I have the K110 with the kit, and the kit lens quality varies over its range and apertures. It can produce good images, but judging from the background and the EXIF supplied for the one photo, these photos are wide open, where it is not so good. My indoor photos with the onboard flash are much sharper with the kit than your samples, but I also have less pixels. Like others have mentioned, hard to tell without EXIF whether your camera/lens are operating as designed or not. And without the EXIF and the identical scene hard to compare it to the Oly.
01-11-2010, 03:17 PM   #36
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Hello.
żAre you still thinking that is something wrong with your camera or lens?
żDid you try to take a picture using manual focus on live view mode?
Maybe using manual focus you can center your atention in others problems, because you know that focus is going to be correct.

I am thinking to buy a Pentax K-x, but I have seen than soft images is no a very strange thing on this camera. I hope there is a reason to that (and I hope there is something to fix it).
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