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snorrish
14th of February 2004 (Sat), 01:01
Hi…I took some photos earlier this evening just to mess around with some night shots, and noticed that a few of them had some strange red and blue dots in them. Does anyone know what’s causing this (is it avoidable)?

The camera used is a Canon Digital Rebel, unknown settings.

http://www.planethalflife.com/redef/photos/small1_img_0449.jpg
http://www.planethalflife.com/redef/photos/small2_img_0449.jpg

Here's the original, it has been resized and compressed quite a bit so the colours of the dots aren't nearly as distinct.

http://www.planethalflife.com/redef/photos/img_0449.jpg

Also, here's another photo that i took, just in case anyone want to see another from the series:
http://www.planethalflife.com/redef/photos/small_img_0450.jpg
Original (resized and compressed):
http://www.planethalflife.com/redef/photos/img_0450.jpg


Thanks, any comments are appreciated!

Radtech1
14th of February 2004 (Sat), 01:37
Start by taking several images and look to see if the same colored dots are in the same spot (ie, upper-right quadrant, etc) on all the images. If that is the case, then you can at least narrow it down to a CMOS problem. If that is not it, then I am stumped.

snorrish
14th of February 2004 (Sat), 02:09
the dots can be reproduced, and are in the same spots

here's another sample (intentionally black), full resolution lightly compressed:

http://www.planethalflife.com/redef/photos/img_0458.jpg

EoSD30fReAk
14th of February 2004 (Sat), 10:12
Well it looks like you C-mos has some hot pixels!
if they don't bother you to much i would leave them but personaly i would send it to canon for repair.
i had it once with an Ixus V3, but that was just 1 hot pixel it was right in the middle of each photo :? but you got 5!! if your camera is still under warrenty i would strongly reccomend you to send it in!!

peter/c
14th of February 2004 (Sat), 14:28
I also have a 300d (rebel).It tells You somewhere in the manaul, if My memory serves Me well,what percentage of 'Hot pixels' Canon accepts as permissible.Mine has only ever shown one and I believe it is only a problem with Long exposures. My advice would be either ring Canon for guidance or just 'clone' out the dots.

KO_300D
14th of February 2004 (Sat), 19:54
Just before it goes back to Canon, if you choose that route, can I ask if you've changed lenses at all?
I'm thinking that very small water particles on the lens (possibly on the inside, the bit that contacts the camera) could cause this as water is known for it's colourful rays when contacted with white light.

I'd try another lens, and if the issue is still there, and you've cleaned the mirror screen inside (very gently!) then I'd go with the Canon service centre option.

snorrish
14th of February 2004 (Sat), 23:22
I don't have another lense to try :(

I have cleaned the lenses/mirror.

I may bring it in early next week...it isn't an enormous hassle (bring it to the store where i purchased it, as i also purchased an extended warranty)...but ill be without it for a month at least.