KirkV said:
Sounds like a bit of a hand full, but if you could explain the process
would appreciate.
SNIP
Okay. See below.
Assuming you use the Minolta DiMAGE Scan utility (V1.13 is current), and
assuming it works the same with the OP's Multi Pro as it does with my
DSE-5400.
Set the preferences to Color depth: 16-bit linear. This will produce a
48-bit RGB file.
For this example I'll walk through the scanning of an HD200 color negative
film, each film has it's own settings, even if it's the same type. Allow the
scanner to warm up, and reinitialize (Ctrl+Shift+I).
Place the color negative film in the stripholder in such a way that the
film's between frame space is visible, and make sure that color positive as
film type is selected at the top. Make an index scan and select the frame of
your choice for a prescan by double clicking on it. The preview has the
usual orange yellow color. The brightest part of the frame is of course the
between frame space, because it didn't receive any exposure in the camera.
In my case it has an average color of R:229, G:151, B:108 but each film is a
bit different. Refocus.
Now go to the Exposure control tab. You'll see that the histograms are empty
at the bright end. As a start, I set the following exposure adjustments:
Master +2 , R -1.6 , G -0.3 , B 0.6 , and I hit the Apply settings button.
If I now sample the color of the film base, I get a color of R:252, G:253,
B:250 . You may need to tweak the slider values a bit to get almost equal
RGB numbers as close to, but lower than, 255. The film base is now close to
neutral, so if we later invert the scan in a photo editor, the filmbase
color is practically eliminated. These exposure settings can be used for the
entire film, untill you re-initialize. The exposure level is almost
optimized, which will minimize scanner- and the photon shot noise in
relation to image signal. This all does asume a correctly exposed negative,
overexposed/dense negatives may need a little extra exposure.
Now reposition the filmstrip in the holder to mask the between frame space
(it will reduce the chance on loss of contrast due to flare), refocus, and
do another prescan of the same frame. Crop the image to your liking, and
scan.
You now have a linear gamma, close to blackpoint adjusted, 16-bit/channel
'Raw' file that needs to be postprocessed to get the final gamma adjusted,
tonemapped and color balanced image. Photo editors that can process 16-b/c
files, or a program like VueScan can be used for those final steps.
Bart