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03-28-2017, 08:01 PM   #1
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Getting weird red/blue/green colored pixels on pictures in camera on K-01

They show up all over the place in the camera preview but only a few show up in the final image in lightroom.







First one is green dot second is red dot. That's what they look like but they show up a ton in camera.

03-28-2017, 08:41 PM - 1 Like   #2
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Looks like defective pixels on the sensor. They can be mapped out, see page 194 in the manual "Correcting Defective Pixels in the CMOS Sensor (Pixel Mapping)". The number of defective pixels increases over time as the sensor wears.

Some post processing software maps out the defective pixels which is why they often go unnoticed even without the in-camera pixel mapping.
03-28-2017, 08:44 PM   #3
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QuoteOriginally posted by Ole Quote
Looks like defective pixels on the sensor. They can be mapped out, see page 194 in the manual "Correcting Defective Pixels in the CMOS Sensor (Pixel Mapping)". The number of defective pixels increases over time as the sensor wears.

Some post processing software maps out the defective pixels which is why they often go unnoticed even without the in-camera pixel mapping.
So does this spell dooooooom for my sensor any time in the near future? What's the usual expected amount of these kinds of defective pixels given that I haven't used my camera that much with only a bit over 10,000 shots.
03-28-2017, 09:02 PM   #4
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I'd venture that the CMOS sensor will outlast your camera which will fail for other reasons before the number of defective pixels become an issue.

CCD sensors developed defective pixels quicker in my experience. My 2003 vintage *istD has a good number of them, but even then Adobe Camera Raw can take care of them and map them out. The *istD has no in-camera pixel mapping function so you get to see the multitude of bad pixels when you open the files with software that doesn't zap them.

03-28-2017, 09:15 PM - 1 Like   #5
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QuoteOriginally posted by ZombieArmy Quote
They show up all over the place in the camera preview but only a few show up in the final image in lightroom.







First one is green dot second is red dot. That's what they look like but they show up a ton in camera.
The reason why the count is lower in Lightroom is because the software treats many of the hot pixels as noise.

QuoteOriginally posted by ZombieArmy Quote
So does this spell dooooooom for my sensor any time in the near future?
You might want to try the Pixel Mapping feature: menu/setup 4/Pixel Mapping

Page 194 in the user manual covers this feature. In short, the camera detects the hot pixels, maps their location and removes them from the image. Data from adjacent pixels is copied into the empty space.


Steve
03-28-2017, 10:35 PM   #6
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QuoteOriginally posted by stevebrot Quote
The reason why the count is lower in Lightroom is because the software treats many of the hot pixels as noise.



You might want to try the Pixel Mapping feature: menu/setup 4/Pixel Mapping

Page 194 in the user manual covers this feature. In short, the camera detects the hot pixels, maps their location and removes them from the image. Data from adjacent pixels is copied into the empty space.


Steve
Thanks, I'll look into this once I get the chance.
03-28-2017, 11:03 PM - 1 Like   #7
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From personal experience, lots of long duration exposure shots bring on a few of the stuck pixels, and possibly doing heaps of video.

I've used the Pixel Mapping feature twice since new, could do with it again soon, works well.
03-28-2017, 11:05 PM   #8
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QuoteOriginally posted by PiDicus Rex Quote
From personal experience, lots of long duration exposure shots bring on a few of the stuck pixels, and possibly doing heaps of video.

I've used the Pixel Mapping feature twice since new, could do with it again soon, works well.
Yeah it manifested with long exposure shots. I haven't done it at all since I got it so I guess I gotta get around to it

03-29-2017, 04:30 AM   #9
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Did you use noise reduction? Pages 89 and 91 of the manual.

The shots show 'normal' high ISO/long exposure noise, albeit with a few dead pixels thrown in.

Last edited by JohnX; 03-29-2017 at 04:42 AM.
04-02-2017, 09:35 AM   #10
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QuoteOriginally posted by ZombieArmy Quote
Yeah it manifested with long exposure shots
They're so addictive on K-01
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