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Old Jan 19, 2003, 6:24 PM   #1
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Default dead pixel?

Found what has to be a dead pixel on a dark section of a messing about indoor no flash image.A bright white dot when zoomed becomes a slightly yellow square .This is a 3 month year old c4000.Do you accept and take it out you would never see it in a normal shot.Do you pixel map or scream at olympus.Reading the forums its something i have been very conscious of.

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Old Jan 20, 2003, 8:48 AM   #2
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On reflection is "hot " pixel a better description.

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Old Jan 20, 2003, 8:52 AM   #3
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I would say that you have a hot pixel. You can go into the menu and use the pixel mapping program. This is what Olympus will do if you send them the camera.
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Old Jan 20, 2003, 10:23 AM   #4
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I recently found one or two hot pixels on my Minolta 7i. I can even pinpoint which date and on which picture # they appeared for the first time.

Does anyone know if Minolta has a pixel mapping utility like the one described above? I've never heard of this technique before.

Thanks,

- Paul
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Old Jan 20, 2003, 11:37 AM   #5
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I assume pixel mapping will eliminate the offending pixel which reduces by one the amount purchased.Does anyone know the drill for checking ccd,Irememember reading about it in a forum here or dpreview but cant recall the drill to achieve a black image to highlight hot pixels.
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Old Jan 20, 2003, 4:30 PM   #6
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Talking to myself a wee bit tried a couple of images against a dark wall 1&2 sec exposures two little white dots about the same distance apart but not on the same spots.Ignorance is making me wonder if paranoia is not a bit involved here .

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Old Jan 20, 2003, 9:33 PM   #7
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jasm

If they are hot pixels they should show up in the same place. The colors may vary but the hot pixels should not move.
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Old Jan 21, 2003, 4:46 AM   #8
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Default dead pixel?

I have a similar problem with my Canon A40. I was on another website and they called this effect, problem or whatever way you want to label it as 'Blue noise chunks'. It appears in the dark areas of images I have taken and is more pronounced if I use the Slow Synch shutter/flash? or a shutter speed slower than 1/8 sec. It does have a blue colour and appears in the bottom righthand corner of the images. My question is, is it a defective pixel or is it just a by product of using the above flash/shutter speeds?

Rimbo 8)
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Old Jan 21, 2003, 5:56 AM   #9
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Default blue pixel

I just bought an Olympus C-4000 yesterday. Yes, I was very excited, but also a bit disappointed... because after taking a few pictures, I noticed a blue dot at the same place in every picture. I'm assuming it's a pixel problem.

:? Is this the "hot pixel" you were talking about? Then what is it called when a "pixel is overexposed and blown out forever"? (It is something I read somewhere... can't remember)

I'm going to figure out the pixel mapping thing and see if it doesn't fix it. I was going to exchange it today, but I'll see if I can fix it....
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Old Jan 21, 2003, 2:13 PM   #10
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I probably wouln't worry if I had to map out a couple of pixels. But if more come back, then you should be concerned about degradation. Mapping out isn't like re-birth - it's really about concealing a problem found in most mass produced consumer ccd chips.
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