Digital BW, The Print

Noise becomes more apparent because of the effects of posterization 
as you edit the image.

Chromatic noise which is barely noticeable when the image is loaded, 
for example, can be quite obvious as clumping or graininess after 
levels adjustments, curves adjustments, hue/saturation adjustments 
precisely because you are selectively expanding some information and 
selectively compressing other information. What starts out as 
continuous or near-continuous tones becomes less so. This effect 
will be more exaggerated with an 8-bit image than a 16-bit image.

Cheers,

Mitch 

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Paul D. 
DeRocco" <pderocco@i...> wrote:
> It really depends upon how noisy the image is to begin with. If 
you start
> with an image from a cheap digicam, then the noise will drown out 
any
> posterization. If you start with an image from a good scanner or a 
DSLR,
> then posterization is possible. I've seen it.
> 
> --
> 
> Ciao,               Paul D. DeRocco
> Paul                mailto:pderocco@i...