Lime green pixel problems

[random one]

Hi, i have noticed recently that all of my night shots (i guess all of my pictures actually. i just only notice it in the very dark shots) have a bunch of lime green dots all over them when i'm looking at them on my computer.

i never noticed this the last time i took a bunch of night shots (about a month ago).

when i load the .RAW files into canon's DPP the dots are all lime green, but after i export the pics as .jpegs the dots show up as white dots (there was one large green dot that ended up turning into a small white X.)

what is causing the green dots? i have noticed recently that my sensor might have some dust on it. could sensor dust be causing this? or is it an actual problem with the sensor?

http://i588.photobucket.com/albums/s...IMG_4775-2.jpg

http://i588.photobucket.com/albums/s...IMG_4785-2.jpg

i uploaded a couple examples as .jpegs, with the dots circled. just imagine the white dots as being lime green

(the shot with the flashlight drawings was 1 of about 6 or 7, and they all had the dots in the same place. so it wasn't because of the flashlights aiming at the camera.)

[freygr]

These may just be hot pixels (long exposures). You need to check if they show up in your day time exposures, as if they do you have a failure of those pixels.

[Photo-John]

Definitely a hot pixel issue. They're easy enough to clone out, so if it was me, I wouldn't worry about it.

I'm not sure which Canon camera you're using, but I looked through the menus on my EOS 50D to see if there was a way to deal with the pixels there. Unfortunately I couldn't find anything. There are tools for removing dust - but this isn't a dust problem. Dust on the sensor is always darker than the background. There's also noise reduction. But I don't think hot pixels aren't actually noise. I think the Olympus DSLRs actually have a tool for mapping hot pixels and deleting them from the file. But my 50D doesn't appear to. Anyway, like I said, it's easy enough to clone them out.

[random one]

i can't see them in my day shots. if they're there they must just be blending in really well.

and i agree that it's not a really big issue. definitely not big enough to go without my camera for a month while it's sent back. i guess i'll just be spending more time cloning.

oh, and i'm using the 40d, and it also doesn't have any option for erasing the pixels.

[gryphonslair99]

Hot pixels are common with long exposures. The best way I have found to deal with them is in post processing DPP has the ability to remove hot pixels easily. If you use noise reduction in camera then you exposures will take at least twice as long to take and finish processing in camera. Post processing you have much more control over the process and can take care of individual pixels rather that applying noise reduction to an entire image.

[freygr]

What the noise reduction is it takes the image then exposures a second image with the shutter closed. In the camera the noise exposure us subtracted from the image. Technically this should remove the hot pixels. I would try it myself as it's just a on/off setting. If you don't like the changes you can alwas turn it back off.