Not to denoise.
Only in special cases, where the image could use a bit of blurring and such.
But 99.9% of the time, no. Absolutely no.
Denoise smudges the art and ruines the tones.

You can use other methods that may require more time, but ultimately make the scan look better.
Even if it's a magazine scan, I'd rather see all the specs than have it denoised.
It's a head ache.

Hrodulf and Bjornolfr, you will not be forgotten.
[img]http://i411.photobucket.com/albums/pp199/SyberAngelGabrielle/couplesig.jpg[/img]
[color=black]And if the world were black and white,
you would be my rainbow in shades of grey.[/color]

Click 'n Play!

If I had a fantasy self, it'd be a tentacle monster.