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jasm Jan 19, 2003 7:24 PM

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.


jasm Jan 20, 2003 9:48 AM

On reflection is "hot " pixel a better description.


gibsonpd3620 Jan 20, 2003 9:52 AM

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.

Paul Jan 20, 2003 11:23 AM

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.


- Paul

jasm Jan 20, 2003 12:37 PM

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.

jasm Jan 20, 2003 5:30 PM

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 .


gibsonpd3620 Jan 20, 2003 10:33 PM


If they are hot pixels they should show up in the same place. The colors may vary but the hot pixels should not move.

rimbo Jan 21, 2003 5:46 AM

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)

joy Jan 21, 2003 6:56 AM

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. :cry: 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....

voxmagna Jan 21, 2003 3:13 PM

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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