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View Full Version : In camera noise reduction and when to use it?



eco_bach
02-17-2011, 09:18 PM
In the 7D there are 2 noise reduction options, one for high ISO, and the other for long exposures. I leave both off by default for the following 2 reasons

1-the extra cpu overhead in processing images with noise reduction may cause an issue in some instances with burst shooting and-or low light video+slow CF cards
2-the plethora of 3rd party noise reduction software-plugins which I'm guessing are able to do a more accurate and effcient job of noise detection and removal.

My first question is
Is there ever an instance when it DOES make sense to leave noise reduction on
and
Does in camera noise reduction affect RAW data? I know RAW data is independent of picture style and color balance info, but for noise reduction the answer doesn't seem as obvious to me since noise is not inherent in the light signal, but rather a byproduct of several sensor specific factors.

maarek
02-21-2011, 05:59 AM
H264 encoding does not like noise. I tend to keep my noise settings at standard for the reason that the noise removal is done before encoding. It does not remove that much noise anyway. Keep in mind that the 7d does so fast resizing that a lot of the pixels just disappear through pixel binning. Noise reduction helps so that more of the pixels are used to smoothen out the image. Helps especially for video and gets a cleaner signal out.