You'll typically find answers to this question to be all over the map but I tend to follow Ben Willmore's approach
which says that noise removal/reduction should not be performed not first nor last, but "early."
By "early" he means AFTER you've done global color and tonal correction/adjustments and BEFORE localized editing steps that require selections and masks are performed.
The rationale for doing noise reduction after global color and tone adjustments is that in most cases noise, cannot be accurately evaluated and decisions made on how to remove it, until the tonal adjustments reveal how much noise is actually present in the image. For example, if you do NR first on an underexposed image, and then subsequently adjust exposure/brightness/contrast you will no doubt reveal noise that couldn't be seen when NR was originally done.
Conversely, saving Noise Reduction for last, especially when using automatic selection tools and masks, means that the noise is likely to become embedded in the masks making it more difficult to remove than if NR was done before before masks and selections were done.
Obviously much of this reasoning is workflow-dependent. By that I mean advances in post-processing, like the ability in CS3 to edit both Raw and JPEG files in Adobe Camera RAW, means that you can entirely remove noise and perform capture sharpening even before the image file is brought into Photoshop proper. So if you tend to do your first editing steps in ACR, when NR is performed is not really an issue. But for users of older versions of Photoshop then it becomes more necessary to do NR at the most logical point; after tonal/contrast adjustments are made.
Then it becomes further complicated if you follow Bruce Fraser's sharpening workflow
because then it becomes a concern that the capture sharpening round could tend to exaggerate the amount of noise present in an image.
Of course much of this turns also on how extensive your post-processing is normally. If you don't do masks and selections of specific image elements, or multiple rounds of sharpening, and limit your editing to maybe a few Levels and Curves adjustments then the point at which NR is done becomes less critical.
meady100 wrote in post #5903331
Hi all! This dilemma has been bugging me for ages; is there a definitive best practice in the application order of denoise (neatimage) and (smart) sharpen?! Very interested to hear answers!
Thanks,
Steve