On Jan 17, 2006, at 10:07 AM, Sylwester Pietrzyk wrote:
No. The problem is that silver particles in classic b&w materials
blocks IR
light so resulting picture which is used later as a mask to deduct
flaws
removes not only dust and scratches but also information from the
photo. The
same applies to Kodachrome slide film.
The problem with silver black and white films and the problem with
Kodachrome are two totally different animals. The metallic silver
grains in black and white film don't so much block the IR as scatter
it. This produces incorrect information which the ICE system tries
to act on, resulting in seriously weird looking scans.
ICE is designed to detect and remove surface imperfections on film.
In Kodachrome the emulsion swells differentially depending on how
much dye it takes in. This causes a bas relief effect on the emulsion
side of the film. You can see this if you direct a bright light
obliquely onto the surface of a Kodachrome trannie. ICE interprets
this bas relief effect as surface defects and attempts to remove
them. Obviously, the amount of bas relief effect depends on the
image, which is why Kodachrome scans just fine with ICE in some cases
but not in others.
Bob (who was alpha and beta tester of Digital ICE)
