Digital BW, The Print

on 12/18/02 9:21 AM, Stephen Kobrin <skobrin@...> at
skobrin@hotmail.com wrote:

> At times, I notice posterization -- a very grainy look -- typically
> in areas of sky when the image is scanned.  For example, I scanned an
> image with a large area of gray, cloudy sky where the posterization
> (or break-up) was obvious in the pre-scan.  I use a Nikon LS 2000,
> scanning at 12 bits (16 in PS) and in this instance the film was
> Ilford HP-5.

Keep in mind that some operations in some scanners that tell you they are
working in high bit are not really working in high bit. I¹m NOT suggesting
this is the case with the Nikon because I really don¹t know. What you can
try to do is find a ³Sweet Spot² (using trial and error) where you try and
get raw high bit data from the scanner and avoid using any of the
curves/corrections provided even if it looks flat and ugly. Then try doing
the corrections in Photoshop on the high bit and see if indeed this is
banding and it¹s showing up due to the way you are setting the scanner. It¹s
possible this isn¹t an issue that has anything to do with scanner control
and high bit. Still worth testing.

Also be sure you have no sharpening on when scanning which might be the
culprit as well. 

Andrew Rodney