Michael Wong wrote:
> The problem is solved upon I disable Infrared clean option. I wonder there
> was no any problem to scan B/W negative film by my Nikon LS-40 scanner with
> Infrared clean option enabled but get problem with my Canon 8800F.
>
> Dunno the reason but working now.
>
Michael, I've been away from the list for a few days. I was just
catching up and about to ask that you try turning off IR cleaning.
IR cleaning can not actually work with silver based B&W film for
physical/optical reasons. IR cleaning depends on the fact that IR is
stopped by dust particles and affected very little by the dyes in color
(and chromogenic (C41 process) B&W film). So the IR scan pass can
differentiate between image details dust, hairs, etc. on the film.
However, the silver particles that form the B&W image are also opaque to
IR light, so practically the whole image is a "dust spot". I suspect
that VueScan hasn't crashed, but is engaged in a futile attempt to work
with endless dust correction. Leave it a couple of days, and it may
complete - leaving a useless image.
You may ask why it allows you to choose IR cleaning with B&W. As IR
cleaning does work with the C41 process B&W films, it does need to be
available for them.
I suppose it's also because VueScan is the full tool set for
sophisticated users, and allows you to do even dumb things if you want.
For example, the dyes in Kodachrome also block IR although not as
strongly as silver based B&W. I found that IR cleaning can do a nice job
of cleaning up the skies on some old Kodachrome slides while introducing
artifacts in the darker parts. So I could combine to scans, one with and
one without IR cleaning, to get clean skies.
Your Nikon software probably just ignores the IR clean setting with B&W
film. I also recall that there were versions of ICE, on Epsons, as I
recall, that switched to a non-IR based dust cleaning for B&W. In the
Photo-i tests, the results were awful, with poor cleaning and lots of
loss of sharpness.
Moose
==============================================
List usage info: http://www.zuikoholic.com
List nannies: olympusadmin@xxxxxxxxxx
==============================================
|