Hot Pixels on 40D

thengz · 21st May 2008

Hey guys,

Not sure if I'm the only person experiencing this but today I took some long exposure shots at night, and there is an orgy of hot pixels on my pictures. They occur on the darker parts of a picture and starts becoming somewhat visible at 2.5 seconds exposure.

At 8 seconds they are even more prominent. By 20 seconds, its like a whole mass of hot pixels having their very own bonfire/bbq/Ku Klux Klan-gathering on my picture.

The funny thing is, when I export the RAW file to JPEG using Lightroom or Photoshop, all the hot pixels are gone. So I can't upload a sample here. Might just be the programs doing their thing (aren't they great?

)

Just want to know if anyone have experienced this on their 40D and if so, what did you guys do to clear this problem. I've read in previous threads that we can send to Canon for sensor mapping. Not sure what exactly that means, but seems like it helps. If that doesn't clear the problem, does it mean that I have to change my sensor?

P.S. If you guys are going to advice me to go and shoot more, don't be bothered about the small problems, do more of my own research, etc, etc, please don't bother posting. I need some constructive comments here, not comments that you think will make you sound deep but in actually just expose yourself as a dimwit that talks in circles.

Links to any other useful threads/websites would be greatly appreciated.

donkuok · 22nd May 2008

Fast asnswer: Send in your cam to CSC to remap. It's free.

shahrulesa · 22nd May 2008

Are you talking about hot pixels or noise? If you take RAW the noise is not filtered out until you convert to JPEG.

thengz · 22nd May 2008

Originally Posted by shahrulesa

Are you talking about hot pixels or noise? If you take RAW the noise is not filtered out until you convert to JPEG.

I'm pretty sure it isn't noise. Its consistently on the same spots for all my shots. Oh yes, I left out another detail, the shots were all taken at ISO 100.

alternatve · 22nd May 2008

I don't have this problem with my 40D. It may be time to send your 40D in for servicing...

Samuel

thengz · 22nd May 2008

Originally Posted by alternatve

I don't have this problem with my 40D. It may be time to send your 40D in for servicing...

Samuel

Yikes... OK. Thanks for the info. Seems like I'll need to do some sensor mapping at Canon then.

21st May 2008	#1
thengz Member Join Date: Aug 2007 Posts: 786	Hot Pixels on 40D Hey guys, Not sure if I'm the only person experiencing this but today I took some long exposure shots at night, and there is an orgy of hot pixels on my pictures. They occur on the darker parts of a picture and starts becoming somewhat visible at 2.5 seconds exposure. At 8 seconds they are even more prominent. By 20 seconds, its like a whole mass of hot pixels having their very own bonfire/bbq/Ku Klux Klan-gathering on my picture. The funny thing is, when I export the RAW file to JPEG using Lightroom or Photoshop, all the hot pixels are gone. So I can't upload a sample here. Might just be the programs doing their thing (aren't they great? ) Just want to know if anyone have experienced this on their 40D and if so, what did you guys do to clear this problem. I've read in previous threads that we can send to Canon for sensor mapping. Not sure what exactly that means, but seems like it helps. If that doesn't clear the problem, does it mean that I have to change my sensor? P.S. If you guys are going to advice me to go and shoot more, don't be bothered about the small problems, do more of my own research, etc, etc, please don't bother posting. I need some constructive comments here, not comments that you think will make you sound deep but in actually just expose yourself as a dimwit that talks in circles. Links to any other useful threads/websites would be greatly appreciated.

22nd May 2008	#2
donkuok Member Join Date: Oct 2004 Location: Perth, Australia Posts: 902	Re: Hot Pixels on 40D Fast asnswer: Send in your cam to CSC to remap. It's free. __________________ Canon EOS 40D + Batt grip

22nd May 2008	#3
shahrulesa Member Join Date: Dec 2006 Posts: 621	Re: Hot Pixels on 40D Are you talking about hot pixels or noise? If you take RAW the noise is not filtered out until you convert to JPEG. __________________ Shahrul Esa

22nd May 2008	#5
alternatve Member Join Date: Dec 2006 Posts: 1,311	Re: Hot Pixels on 40D I don't have this problem with my 40D. It may be time to send your 40D in for servicing... Samuel __________________ f/8 and be there.