[APML] Scanning AP slides with Vuescan

["Greg Hartke" <ghartke@earthlink.net>]

I decided that the software that came with my Nikon Super Coolscan 4000 ED
was insufficiently flexible to get maximum information from AP slides shot
on E200 so I bought the Vuescan software. This seems much better but I'm not
convinced that I'm doing a good job scanning my slides yet. Good scans are
the first step in good processing so I'd like to ask for advice in using the
Vuescan software to get the best scans possible.

Several questions suggest themselves immediately though I'll be happy to
hear any comments on the subject. Under the "Color" tab, should I be
adjusting the brightness of the individual colors to align the peaks in the
histogram or should I just adjust the levels in PS? What "Image curve"
optimizes the scan? Naively I would expect that you'd want to pick the curve
that moves the histogram such that the values are not bunched at the low
end. In general I would expect one of the logarithmic curves to be best to
stretch the histogram but how is the best curve chosen? (Choices are
"Gamma", "Log (dark)", "Log (medium)", and "Log (light)".) I've never tried
setting the black point; I've been doing this in PS. Should this be done at
scan time? I find the flexibility of choosing the TIFF file type to be
interesting. What's a good choice here? The appropriate choices for color
slides would seem to be among 24 bit RGB, 48 bit RGB, and 64 bit RGBI.

I don't seem to be hardware bound in either scanning or processing. The
scanner has Firewire so scans are quick no matter what I do. I also seem to
have sufficient RAM (512 MB) and sufficient processor speed that processing
steps in PS proceed quickly.

FWIW, I've been using "Color balance" = none and the color space is sRGB for
file, monitor, and printer.

Thanks!

Greg