Comments on: How does ‘Noise Reduction’,NR for long exposures work? http://www.woolyinc.com/noise-reduction/how-does-noise-reductionnr-for-long-exposures-work Sound Barriers and Noise Reduction for Home Music Studios Sat, 19 May 2012 09:45:25 +0000 http://wordpress.org/?v=2.7 hourly 1 By: Kevin K http://www.woolyinc.com/noise-reduction/how-does-noise-reductionnr-for-long-exposures-work/comment-page-1#comment-4011 Kevin K Wed, 11 Aug 2010 12:03:59 +0000 http://www.woolyinc.com/noise-reduction/how-does-noise-reductionnr-for-long-exposures-work#comment-4011 It takes an exposure for the same time as the original exposure, without letting any light hit the sensor (black frame). Then it looks at the dark image, and sees where there are any bright spots or hot pixels. Then it goes into the original image and fixes the individual pixels. It works best if the temperature is constant throughout the two exposures. Do a search, some people have modified their cameras with Peltier chips to keep the sensor cool. The other way to do it is shooting on cold nights, much less sensor noise. here's a 12 minute exosure, almost no noise, 17 degrees outside: http://cgipix.com/Portfolio_Utah_Vacation_Travel_Arches_Canyonlands.htm<br><b>References : </b><br> It takes an exposure for the same time as the original exposure, without letting any light hit the sensor (black frame). Then it looks at the dark image, and sees where there are any bright spots or hot pixels. Then it goes into the original image and fixes the individual pixels.

It works best if the temperature is constant throughout the two exposures.

Do a search, some people have modified their cameras with Peltier chips to keep the sensor cool. The other way to do it is shooting on cold nights, much less sensor noise.

here’s a 12 minute exosure, almost no noise, 17 degrees outside:

http://cgipix.com/Portfolio_Utah_Vacation_Travel_Arches_Canyonlands.htm
References :

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