Digital BW, The Print

You may want to try a dedicated noise-and-grain-reduction plug-in. "Neat 
Image" works great for grain reduction. It's available at several price 
points, with the Pro version providing Photoshop plug-in functionality. I 
prefer it to "Grain Surgery", "Quantum Mechanic Pro", or "Applied Science 
Fiction Digital GEM" (great names, eh?) after having tested all four. Very 
effective grain reduction, very controllable, works great on 
black-and-white images, and the latest version works more quickly than 
earlier versions. I also think its price is lower than the other programs 
(though I'm not sure).

I usually duplicate a layer, run "Neat Image" and blend the grain-reduced 
layer with an unprocessed layer to visually adjust for the best compromise 
between grain reduction and the preservation of a certain photographic 
look. For a uniform area like your overcast sky, you may want to select the 
sky, feather the selection, and set "Neat Image" to almost entirely 
eliminate the grain.

http://www.neatimage.com/index.html?v

"Neat Image" is PC only, though I presume that someone probably publishes 
Mac software with similar functionality. Others may want to make Macintosh 
recommendations...

At 01:32 PM 1/24/2004, marcsien77 wrote:
>I would greatly appreciate advice on a PS technique to reduce grain
>from an almost uniform overcast sky area of a BW image.  The rest of
>the image is fine so I was thinking of doing something with a layer
>mask but so far I had no luck.  Many thanks in advance, Marc.