On Fri, Sep 26, 2003 at 05:09:30PM -0700, Daniel Rogers wrote:

It depends on what kind of noise you are looking at. Can you describe the noise more precisely? Is it "salt and pepper" noise? Gaussian noise? If you can show an example image I can help you pick a filter.

I'm not sure I know how to describe it. I was really just asking in general terms although there is a specific image that prompted my question. Take a look at my web site at http://craniac.afraid.org and look at the very first photo there, the one with the red buildings. I used the curves on the sky section to give a similar effect to using a polarising filter. This has accentuated noise that isn't too noticeable in this small, low-res version but is quite noticeable in the full-sized original and would probably be noticeable on a print. As this is a reasonable flat area of colour the Gaussian blur filter could work but might not be the best thing to use for other images.

I think that what I'm looking for is some ideas/tutorials on different techniques that would suit different cases. I don't much care for a script that is more generic. After all if I wanted the canned approach I could just use Windows and Photoshop with it's million and three filters. I prefer to understand why the technique works as this will aid me in applying it to future, slightly different cases.