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nwhc
12-12-2012, 9:23am
Hi All,

I had a play with shooting stars last night, looking at the pics now there is about 8 bright red pixels on the images.

Is this a permanent issue? should i send the camera back to where i bought it?

It is a 5D mkii only about 5 months old hardly had any use.

thanks for any advice.

Karl

Cris
12-12-2012, 9:35am
I presume you were using a long exposure, in which case they are probably hot pixels caused by the long exposure, just clone them out and it is nothing to worry about. At least I dont anyway. Hope this helps.

nwhc
12-12-2012, 9:38am
Well it was 25 sec so not super long exposure, I'm not to concerned but like to have peace of mind :2smile:

ricktas
12-12-2012, 1:22pm
Bright red is not a stuck pixel, it is a 'hot pixel' and is often seen in long exposure shots. It can be caused by the sensor heating up during the long exposure. You can, in most cameras' (check your manual) run a thing called 'long exposure noise reduction' that will often pick these pixels up and remove them from the file.

The other pixel issue you can see is either a white or black one, and this is referred to as a dead pixel and can be solved by running 'pixel mapping' from the camera menu.

ving
12-12-2012, 2:14pm
i wouldnt have thought that a 25sec exposure would be long enough to get a hot pixel but i suppose it depends on ambient temperature too.

nwhc
12-12-2012, 2:25pm
i wouldnt have thought that a 25sec exposure would be long enough to get a hot pixel but i suppose it depends on ambient temperature too.

There was numerous 25 sec exposures so i guess it would build up over time, will have another look tonight.

Steve Axford
12-12-2012, 2:49pm
25 sec is heaps long enough for hot pixels. Rick has the right answer for this one, but remember the camera gets rid of the problem taking a dark frame and subtracting it from the real frame - so it stops you from taking photos as fast.