Digital BW, The Print

This could be a number of things. Do you scan in 16bit? When you say 
boost in local contrast does that mean you are using the "brightness/
contrast" adjustment? If so, you should use curves instead so as to 
only affect the tones you want to. But doing all that really just hides 
the posterization. The actual cause might be in the scanning, the 
negatives themselves, or the transfer curves you are using which I have 
no idea about since I use the piezography plugin.

-mh

--- In DigitalBlackandWhiteThePrint@y..., "oncdoc301" <oncdoc@c...> 
wrote:
> Hello,
> 
> I am a new digital B+W printmaker employing an Epson 2450 to scan 
> 6x9 and 4x5 negatives into Photoshop 6 printing to an Epson 1280 
> employing the MIS variable mix hextone inkset.
> 
> I employ the Silverfast scanning utility which shipped with the 2450 
> allowing the software to determine a file size which for any given 
> image size allows a resolution of 320 dpi. I utilize the custom 
> settings on the Epson printer driver specifying 1440 dpi.
> 
> Although I have been pleased with the output for the most part, I 
> have noticed a bothersome tendency to posterize dense mid and 
> darktones such as might occur in a tree line or a bed of salt grass 
> in a shore scene. I have noted that a boost in local contrast can 
> correct this in large part, but this is a nuisance and compels 
> increasing local contrast to the point where dark tones tend to 
> merge.
> 
> Any explanation or suggestions would be greatly appreciated.
> 
> Thanks.
> 
> Stuart