In rec.photo.film+labs Chris Sprague wrote:
The answer to this question is in my follow-up post, the second post in
this thread (Epson Perfection 3200, Vuescan). I let Vuescan chose the
exposure and colors, and since they were very close to what I saw on
the film, I made no adjustments. From there the only thing I did was
downsample and save to jpeg for the web.

Smart, using 1:1:1 chroma subsampling on the JPEG. I don't know
what software you used to write the file, but (for JPEG) quality is
about as good as it could be. Thanks again.

I'm a little puzzled why people continue to like Velvia 50, because
for me, the pink cirrus clouds ruin that image. The forest is not
objectionably magenta in the Velvia 100; warm colors are good.
The sky was deeper blue with Velvia 100, but that could have been
owing to exposure (EI 40 with Velvia 50).