Thanks Mark. Audio denoising... Hmmm.

@Mihuel can you share your CS5 (Soundbooth?) audio workflow?

Video noise patterns are characteristic of each camera model's image sensor and compression chain. Neat Video can save noise profiles for each camera type at specific ISO settings. If you're applying noise reduction to a batch of video footage, it's a good idea to standardize on a consistent set of noise profiles. This type of noise reduction should be applied before any other post-production manipulation of the image.

Sharpening is needed to compensate for the cummulative low-pass filtering effects of scaling and color correction operations. Mathematically, anytime that pixel values are averaged or combined, it rounds off the sharpness of edges. Ideally, you'd want to apply sharpening after the results of all other post-processing effects.

@Mihuel Absolutely agree on your audio analogy although I think I'd normalize first if the levels weren't quite right, as otherwise you don't know how much noise reduction to apply. And yes, then reduce noise and then do anything with dynamics after noise reduction. Similarly in video, I normally get the levels adjusted before applying noise reduction, and then do other things to the video. And yes, sharpening last of all.

With both video and audio, the secret is to know how much NR to use, as too much introduces artefacts. Same with sharpening of course!

In terms of the original question, I'd sometimes use sharpening on different clips to match them together, and then probably an overall but VERY gentle sharpening last of all, using a convolution matrix as it's very light on the processor.

@sam_stickalnd
thanks

From: http://www.neatvideo.com/qna.html

Q :Is processing via Neat Video best done before or after any other processing (i.e. tonal/color correction)?
A: Such operations as tonal/color correction are quite conservative from the standpoint of noise, i.e., they do not significantly change the noise characteristics of the video sequence. Therefore, filtering before or after makes little difference – as long as the noise profile is built and applied at the same stage of your workflow. For example, don’t use a device noise profile built with an unprocessed (the color correction is not yet applied) video sequence to filter the same sequence with the color correction applied.

On the other hand, certain effects, like sharpening or resampling, applied to a noisy video sequence may considerably change its noise properties. In this sense, it is generally better to use Neat Video filtration before applying such effects.

Question is to denoise before color/expo../curve or after ?

@stonebat
This my personal opinion so it is not a voice of professional
1) settings - always on the eye - as suits me - less is better
2) apply after denoising and color/exposure/curve correction
3)always last