pcassity Posted November 16, 2018 Share Posted November 16, 2018 Can anyone explain the noise reduction process for a Nikon DSLR. I certainly understand that one can chose the level of noise reduction but I am wondering how the electronics of the camera determines when to use it. Or, is there a specific level of noise reduction applied to all jpegs regardless of whether is needs it or not, based on what one has selected? If the camera applies noise reduction, does it increase the sharpening to compensate for any noise reduction applied? Link to comment Share on other sites More sharing options...
Ed_Ingold Posted November 17, 2018 Share Posted November 17, 2018 There are two types of noise reduction in a Nikon (and most other cameras) - High ISO and Long Exposure - all done in processing. High ISO noise reduction looks for hot and dark pixels, and blends them with surrounding pixels, with a loss of resolution and visible artifacts. Long exposure, in my D3, takes a dark frame, shutter closed, after the shot for the same exposure time. Hot pixels are detected in both frames and cancelled in processing. AFIK, it works for RAW too. I generally leave both off, because I'd rather see noise than worm tracks. 1 Link to comment Share on other sites More sharing options...
JDMvW Posted November 17, 2018 Share Posted November 17, 2018 I generally leave both off, because In my vast or half-vast experience, I find that noise reduction in post processing gives me more control than what the camera does on it's own. 1 Link to comment Share on other sites More sharing options...
pcassity Posted November 18, 2018 Author Share Posted November 18, 2018 As Do I, since I shoot entirely RAW, it really makes no difference if its on or off, though. I am trying to understand how the camera reacts to noise in a jpeg. What I have noticed during some very (unsophisticated) tests is that jpegs straight from the camera, with a normal amount of noise reduction applied, appear to be somewhat cleaner and sharper than images in RAW, and processed in Lightroom. Link to comment Share on other sites More sharing options...
mike_halliwell Posted November 18, 2018 Share Posted November 18, 2018 I thought the great benefits of Dark Frame Subtraction (Long. Exp. NR) cannot be reproduced in any other way? 1 Link to comment Share on other sites More sharing options...
Andrew Garrard Posted November 19, 2018 Share Posted November 19, 2018 I thought the great benefits of Dark Frame Subtraction (Long. Exp. NR) cannot be reproduced in any other way? Than what? I have a lens cap and the ability to do some dark frame subtraction in post that suggest it doesn't have to be automated (though I might not turn down a feature to do this in camera automatically but still deliver the raws). Link to comment Share on other sites More sharing options...
mike_halliwell Posted November 19, 2018 Share Posted November 19, 2018 I thought the theory was that a subsequent (almost simultaneous) Dark Frame removes the noise created by things like thermal effects and such. Doing it two days later is missing the random stuff..... Link to comment Share on other sites More sharing options...
Andrew Garrard Posted November 19, 2018 Share Posted November 19, 2018 I thought the theory was that a subsequent (almost simultaneous) Dark Frame removes the noise created by things like thermal effects and such. Doing it two days later is missing the random stuff..... Oh, I meant taking the capture at the time (if not entirely, if you need a lens cap), just doing the subtraction later. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now