Bart said:Actually, you 'just' need to adjust the "exposure" of the shadow
exposure file, after recording it as a Raw or linear gamma image.
For example:
- Exposure 1 is for the highlights, maximum non-clipped exposure.
- Exposure 2 is for the shadows, say 4x the exposure of Exposure 1.
Now you need to reduce! the presumed linear gamma luminance levels, by
dividing the luminances by 4! This will provide a seamless fit with
the luminance range of exposure 1, if blended in registration. It will
give a linear 16-bit exposure range with superior photon shot noise
characteristics, and 16-bits will cover a density range of 4.8, well
in excess of what slide film can offer.
Instead of a factor of 4, an exposure factor of 8 can be used, but
that increases the chance of blooming, a bit depending on the scanner.
Bart
You might try something like the "Ionic Breeze" ...
http://www.sharperimage.com/us/en/catalog/productview.jhtml?
sku=SI737SNX&hppos=27
....
Having done my share of damage unmounting paper mounts, I know how you
feel. But some of my compositions are so tight that I have to unmount to
expose the 10% image area covered by the mount. Then I found a device
that helps a great deal: Paper Mount Opener, item QM5050, from BCA in
NY, 631-667-8470. This plastic gizmo has a snug channel that lets you
push a slide mount through, while a mounted blade cuts one side of the
mount open without touching the film. Costs a few bucks, and beats the
heck out of using a free hand blade.
This probably works fine for scanners with hardware control over
exposure. But my Polaroid ss4000 offers no such control. My next scanner
will definitely have it, like a Coolscan V or 5000, or a Minolta 5400.
Cliff said:FYI the Polaroid SS4000 hardware definitely has exposure control.
Unfortunatley the Polaroid software offers no manual control. However,
Silverfast AI has always supported it (Options/Special/Lightness), and
Vuescan probably does, too.
Don said:That's *very* interesting! Thanks very much!!!
Of course, that would mean scrapping all the scans I've done so far
and - for the umpteenth time (!) - starting from scratch all over
again. Argh... :-(
Very interesting. How can you tell that Silverfast is changing the
exposure in hw and not in sw? Does Silverfast allow you to change the
exposure BEFORE a preview? Changing the exposure AFTER a preview and
without re-scanning is done by sw.
If this is indeed a fact, then Polaroid is offering this control to a
third party vendor instead of in its own sw. Does not make sense.
I feel your pain. I have re-scan and re-edit some images umpteenth times
with each new trick I learn about scanning or PS. Call it the a learning
curve, or curse!
Cliff said:The exposure ("Lightness") setting directly affects the scan time, and
higher exposure settings capture higher densities in raw files. Yes,
you can change exposure before a preview - Silverfast will then prompt
you to do another preview.
Why not just try the Silverfast demo? (or Vuescan)
I think that I did try Silverfast quite a while ago. But I didn't get
too far because it requires getting an IT8 target to profile the scanner
first. Can I still use Silverfast without creating a profile?