Thread: Photo Help
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Old 08-19-2008, 01:12 AM   #6
nthfinity
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Originally Posted by MidEngine4Life View Post
Yea in its raw large size before i resized it there were a lot more visible. Im using an Olympus E-500. I was using the setting that lets me select the shutter speed and it compensates for the rest. Set it at the max of 60 seconds.
OK

what is happening with long expsoures is the CCD ends up heating up, and more pixels become "hot" and expose in misc colors.

60 seconds is a LOT of expsure time. Tolerences change in mfr. spec with the more exposure time you have there is less mfr. spec for hot pixels... i hope that makes sense.

that said, the number is pretty outrageous IMO... seems you aren't the only guy with this issue

http://photo.net/olympus-camera-forum/00LYDX

In my canon, there is an option for "color noise reduction" on long exposure. It's already so low that I don't have this set on, even in bulb shots of 200 seconds (i've only done that a few times) ... where basically the software compares the noise in a normal exposed shot compared to the long exposure, and eliminates most of the hot pixels that would form.

so a bit of PS will solve your issue... but unfortunatley, it does seem normal
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