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12-22-2012, 08:05 PM   #1
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Bad sensor?

Hi, i'm getting worry about k-30 sensor. Do you mind check your copy of k-30 for those yellow stains that scattered over my sample. All thoughts will be appreciated.
Cheers.


Last edited by pavpen; 12-09-2013 at 10:14 PM.
12-22-2012, 08:29 PM   #2
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do you mean the image noise? that's perfectly normal, color artifacts along with loss of detail is not uncommon at high ISO settings on any camera. if they show up at low-iso settings with a less-than 100% crop, then i'd be worried
12-22-2012, 08:33 PM   #3
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You most likely are shooting JPEG. The RAW files can get all color noise pretty much cleaned up.
12-22-2012, 08:56 PM   #4
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Along the edge of the window blinds(?) there is a faint yellow line/area--that yellow fringe is chromatic aberration that can be corrected by many software that work on the camera raw data. There is some disagreement on this--but it is likely due to the lens--sensor combination, and certainly is not a camera fault.

12-22-2012, 08:56 PM   #5
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Thanks for prompt response. The shooting was done in raw format, and i would expect the noise more reddish (at least in the dark area of sample.)
12-22-2012, 09:16 PM   #6
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QuoteOriginally posted by dms Quote
Along the edge of the window blinds(?) there is a faint yellow line/area--that yellow fringe is chromatic aberration that can be corrected by many software that work on the camera raw data. There is some disagreement on this--but it is likely due to the lens--sensor combination, and certainly is not a camera fault.
No, i'm referring to the washed out yellow irregular shaped stains, they evenly scattered over all sample
12-22-2012, 11:43 PM   #7
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the less you pixel peep, the happier you'll be
12-23-2012, 12:37 AM   #8
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Slow shutter speeds (1/4s) always seem to be a bit worse for blotchy noise than at faster speeds attained at a wider aperture for the same exposure. There's more time for noise to build up, not sure what it's called in camera sensor terminology, but in analogue signal old school semiconductor terms it was called shot noise. Sensors are bound to vary a bit with regard to this type of noise, and it will be temperature sensitive so if just before this shot you had taken a load of shots or had been shooting video for instance..............

As mentioned, different RAW converters and settings would likely lose most of it. My guess is that this ISO 800 shot was also underexposed and the exposure was brought up in the converter? So, it could really be equivalent to a much higher ISO.


Last edited by SteveB; 12-23-2012 at 12:42 AM.
12-23-2012, 12:53 AM   #9
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Maybe post a image on a solid color subject, cause everything looks fine in that image
12-23-2012, 11:01 AM   #10
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Thank you all for your suggestions. This is my new camera and i want make sure that bad shots are 100% are my fault.
Cheers
P.S.: Original crop with low and high levels adjusted.

Last edited by pavpen; 12-09-2013 at 10:12 PM.
12-23-2012, 11:08 AM   #11
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Is that sample you're showing a 100% crop, or is it larger?
Also,, you're shooting at ISO 800 here, which is not going to be as "clean" as what you'd see at the base ISO.
12-23-2012, 11:20 AM   #12
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QuoteOriginally posted by johnyates Quote
Is that sample you're showing a 100% crop, or is it larger?
Also,, you're shooting at ISO 800 here, which is not going to be as "clean" as what you'd see at the base ISO.
This is 1/5 or 1/6 of the original size.
12-24-2012, 01:37 AM   #13
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QuoteOriginally posted by pavpen Quote
Thank you all for your suggestions. This is my new camera and i want make sure that bad shots are 100% are my fault.
Cheers
P.S.: Original crop with low and high levels adjusted.
That phrase "Original crop with low and high levels adjusted" could explain a lot. I think what you're seeing is the current state of sensor technology - you would get a perfect 11"x14" print from the full size image even after adjusting levels.
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