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Old Sep 8, 2007, 10:25 PM   #1
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Is this normal for the K10D at ISO 800.

Imported with Lightroom. All settings were zeroed (in other words, no adjustements were made), even left white ballance untouched.

Only thing that was done was resized and exported as .JPG at 80% quality settings, and I assure you that what you see here is actually much more subtle than what I see within the original .PEF

Please note the many vertical coloured lines thoughout the shadows, and the VERY pronouced horizontal line along the bottom of the image.

I know that this is far from a "good" exposure, but I have a hard time believing that is is par for ISO 800.

Thanks in advance for any ideas and suggestions.

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Old Sep 8, 2007, 11:44 PM   #2
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I haven't used Lightroom, but since it was shot RAW it's hard for me to say if what you're seeing is a camera or software problem. I use the K100D which has better high ISO performance, but if I took a shot like this at 800 and either lightened it up or set the contrast real low, I would have noticeable shadow noise.

This seems like a lot of dynamic range to try and capture in an ISO 800 shot. I believe the K10 starts at 100, which would be where maximum dynamic range is. The thing to realize is that every time raise the ISO, you're basically chopping off the top half of the histogram, so at 800 you're only using 1/8 of your dynamic range. Taking that into consideration, what little noise is actually in the shadow areas here doesn't seem that bad.
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Old Sep 8, 2007, 11:48 PM   #3
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First, what firmware are you using for your K10? One of the upgrades (don't remember which one) seemed to help with my camera when it comes to the vertical banding. You might as well install firmware 1.30, the latest one out, and it will pick up all the earlier ones. I'm on my lousy laptop monitor so I can't tell what you mean by the horizonal line at the bottom, but I can seethe vertical banding problems in the dark parts of your picture.

My K10 shows a certain amount of vertical banding at 1600, much less when the picture is properly exposed (or even slightly over-exposed). The only time I see it at lower ISOsis when the picture is underexposed and I've adjusted the exposure upwards - thenI see it at 800. But I don't normally see that much unless I've adjusted the exposure. It seems like some cameras are worse about it than others (I'd classify mine as somewhere in the middle/toward bad but not as bas as some I've seen). If your camera is brand new, I'd probably go back to where I bought it and see if another one would be better. Or else send it to Pentax for warranty repair (don't know anyone who's sent theirs in for banding issues, so can't say about possibility of getting it fixed. I thought about sending mine in until I upgraded the firmware and it helped).
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Old Sep 9, 2007, 10:14 AM   #4
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Attaboy wrote:
Quote:
Is this normal for the K10D at ISO 800.

Imported with Lightroom. All settings were zeroed (in other words, no adjustements were made), even left white ballance untouched.

Only thing that was done was resized and exported as .JPG at 80% quality settings, and I assure you that what you see here is actually much more subtle than what I see within the original .PEF

Please note the many vertical coloured lines thoughout the shadows, and the VERY pronouced horizontal line along the bottom of the image.

I know that this is far from a "good" exposure, but I have a hard time believing that is is par for ISO 800.

Thanks in advance for any ideas and suggestions.
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Personally it seems to be common w/ the k10 at high isos/underexposed images. K10 is not the high iso/underexposed shot wonder. Take that statement for whatever you think it's worth. 800 is like 1600 on a 6mp camera and behaves similarily. The banding has been discussed ad-nauseum.If us humans weren't so darn sensitive to pattern recognition it wouldn't be such an issue as it really isn't that bad.
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This would be a tough shotw/ any camera but would recommend a 6mp one
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The line you are referring to is more troublesome though. not sure it's a memory card problem or the sensor. Either way, sending this image and the camera to Pentax would be my recommendation. From my old film days this would be familiar as a scratch from dirty camera backs or a dirty processor. Both of which were all too common for me. Iexaggerated the image to see it better:
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Old Sep 9, 2007, 11:08 AM   #5
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Interesting horizontal line (thanks for bringing it out so my poor old laptop's monitor could show it, and yes it's far more of a concern). The only time I had something like this occur it was with a faulty card, but it was also far more obvious - if you have another card, try something similar and see if it occurs with it, too (take out the possibility it's the card). If it's the camera, it's not normal and should either be returned or sent in for repair.
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Old Sep 9, 2007, 9:37 PM   #6
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Thanks for all the input. I'm gonna drop by the store where I bought my camera this week and see what they say.
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