Building Scanner Profiles - Color Management for Photographers - page 146

films will not be optimal for use with Kodachrome TM . Some have reported good results scan-
ning Kodachrome TM with a profile built using the HCT Fujichrome TM Velvia target. I have suc-
cessfully scanned different film brands using a single profile generated from this target. I asked
Don Hutcheson, the creator of the HCT target, about his opinion of this debate. Don suggested
that the scanner and its filtration characteristics (light source, sensor type, and so forth) play a
role. A Fujichrome TM Velvia target is recommended due to its extended color gamut compared
to Ektachrome TM . If you have the budget and your color requirements are extremely demand-
ing, you may want to purchase multiple targets made from different film brands. For many users,
a target made from a single film brand should suffice. There are multiple brands of Ektachrome TM
and Fujichrome TM (of which Velvia is only one). If in doubt, begin by purchasing the HCT target
made from Fujichrome TM Velvia. If you do plan to scan much Kodachrome TM originals, you
may want to invest in a target made from this film stock. It is available in a 35 mm mounted
transparency.
The Scanner
We need to discuss the scanner software before getting into the details of
the profile creation. How the scanner software is configured to scan the
target is critical. There are a number of issues that affect our ability to
create a viable scanner profile. In virtually all cases, the issues are soft-
ware-related, not the scanner hardware. Due to the software that drives
them, some scanners cannot be profiled. An example of a scanner I could
not profile was the original Polaroid SprintScan. This was due to how the
scanner produced an automatic white, black, and color balance adjust-
ment, which could not be turned off in the software. If I scanned the IT8
target, built a profile, then applied the profile to this scan, the profile pro-
duced excellent color appearance. If I then placed any other piece of film
in the scanner and applied the profile, the results were unacceptable. The
scanner conducted a different white/black and auto color balance setting
on the newer piece of film, vastly altering its original behavior. The profile
that reflected this original behavior was incorrect for this scan. The results
were always poor. Since an ICC profile analyzes and describes the behav-
ior of a device, any deviation in this behavior invalidates the profile. I
was able to use a profile for this Polaroid scanner with a third-party
scanner driver from LaserSoft called SilverFast since it was ICC aware. This
software didn't behave as the supplied Polaroid software so I was able to
profile the original hardware. I mention this because it's quite possible
you might want to profile a scanner driven by software that will not allow
it to be placed into a consistent behavior. In such a case, look for a third-
party ICC-aware scanner driver.
There are three basic scenarios that we encounter when dealing with
scanners and their host software drivers with respect to profiling. The
first was just discussed, that being the inability to keep the scanner from
conducting some kind of auto correction to every scan. The second sce-