350D/Rebel XT hot pixel

[Aviller]

Hi,

already posted this in another subforum but you guys might be able to help me out better. At 30 secs I found this cluster of hot pixels (still noticeable at 15 secs as well, hardly noticeable at 5 secs). Is this something that should be dealt with or is just to be expected?

at 100%:

http://i89.photobucket.com/albums/k217/Aviller71/100percent.jpg

blown up to 800%:

http://i89.photobucket.com/albums/k217/Aviller71/800percent.jpg

I just don't want to return the camera for a new one and then find even more of those...or be w/o the camera for a number of weeks.

[coldrain]

It is normal, and not a cluster... one photo diode not handling prolonged exposure very well, and the surrounding pixels get a bit of its red too in conversion to an image (since it is a Bayer pattern sensor).
So... nothing weird, just something one can see with longer exposures.

[Aviller]

Thanks. I've noticed that noise reduction takes care of the problem at 30secs. At ISO 100, does noise reduction also kick in at shorter shutter speeds?

[coldrain]

That kind of noise reduction you are talking about is long exposure noise reduction, where a dark photo of same duration is taken after the "real" photo, and the noise (and hot pixels) get subtracted from the original image before storage.
I think kicks in at exposure times over 1 second, regardless what ISO setting is chosen.

[Aviller]

Interesting...tried a 20 sec exposure last night with NR on but there was no "2nd image" taken afterwards. According to my manual NR only starts at 1sec if you have the ISO setting at 1600. I wish there was a way around that...

[coldrain]

Interesting...tried a 20 sec exposure last night with NR on but there was no "2nd image" taken afterwards. According to my manual NR only starts at 1sec if you have the ISO setting at 1600. I wish there was a way around that...
I was msitaken.