filmscanners: NikonScan 3.1: how to get good color and shadow detail

["PAUL GRAHAM" <peegee@btinternet.com>]

Bill 
thanks for your NS 3.1 advices,
they are useful,

so what do you suggest as a good everyday practise:
wide gamut (compensated) 
or turning color management off?

I use fuji negative film nearly all the time.

please see my next post on highlight detail and GEM though - my 2 cents...

paul

>>>>>>>>clip>>>>>

DISCUSSION:

(1) By default NikonScan is set up with color management ON and 
outputs files directly to a profiled colorspace such as Adobe RGB. 
However all of the available color spaces reduce the shadow detail.

(2) The "Scanner RGB" color space, which is supposed to mirror the 
raw output of the scanner, produces scans that are dark and have 
wierd color (what you'd expect from "raw" scanner data), but my 
scanner profiler couldn't create a good profile with it, and I wasn't 
able to pull useable shadow detail out of it using Levels.

(3) The "Wide Gamut (compensated)" color space has more shadow detail 
than Adobe RGB, but not as much as with color management off.

(4) With color management off you still have to make the right choice 
from the film-type menu: Negative, Positive or Kodachrome.  The scans 
come out with roughly the right colors and it makes a difference 
whether you choose Positive or Kodachrome so obviously NikonScan is 
doing some color correction of the raw data and making different 
corrections for different film types.

(5) The resulting scans are low contrast but can easily be adjusted 
with the Photoshop Levels dialog.  Of course you want to scan in 14 
bit (rather than 8 bit) mode so that you can make these tonal changes 
without posterizing the image.  After making tonal adjustments you 
can downsample to 8 bits per pixel if you wish.

(6) Comparing two similar scans, one with color management on and 
output to "Scanner RGB" space, the other with it off; if you adjust 
the Levels to grossly lighten the shadows (to see just how much 
detail you've got down there) you'll find that Scanner RGB seems to 
have more tonal gradations in the deep shadows than the no color 
management scan, but with a huge amount of very coarse and 
color-shifted noise.  Therefore the extra tonality of the Scanner RGB 
scans is not useable for making pretty pictures, although it might be 
useful for scientific or forensic use.