Digital BW, The Print

Martin,

This is probably not of great interest to the other readers of this list,
but it always seems the backroom conversations turn out to be interesting.
Also, it fits right in with some of the gamma space conversions Dan C. has
been sharing with us...

I know that like me, you scan in RAW highbit mode (you with a Polaroid 120,
and me with a Leafscan 45), and then post-scan "develop" the file, thus
retaining a toned 16-bit file. I know that you use Silverfast to do this,
and are quite pleased with that program. I've only tested it with a Demo
version, and it'd be a costly add-on purchase for me.

Bruce Fraser shared a gem with me regarding doing the toning in Photoshop.
This pleases me because of the cost savings, but also because I'm familiar
with the interface, and I can zoom in to 100% magnification or more. Anyway,
I thought you might like to try it and see if it works for you.

One thing to note. The directions I post below work very well as-is for me
for transparency materials, short of perhaps a color balance tweak and some
contrast. But since I shoot my negatives routinely to be a stop or so "over
exposed" I still have to make a significant gamma move on them. Not a big
deal, just letting you know that's probably normal if it arises for you too.

From Bruce:

************
(snip)

Your problem stems from the way the Leaf software writes out 16-bit files --
as you've noticed, all the data is bunched up in the shadow end.

Here's what I do with my legacy Leaf 16-bit images: it works fairly well.

1.) Create a linear-gamma profile. I use Adobe RGB as a starting point. With
Adobe RGB set as the working space, in Color Settings, choose Custom RGB,
set the gamma to 1.0, call it something sensible, then save it using Save
RGB. Then restore your working space of choice.

2.) when you open the Leaf image, assign the linear gamma profile.

3.) Go into Curves, set the input value to 4, and the output value to 14.

4.) Use Convert to Profile to convert the image to working RGB.

5.) Edit as necessary.

It's a bit of a kludge, but it works quite well.

************

If you get a chance to try it let me know how it works. I'm still not ruling
out Silverfast for myself, but if this does as well, for free.....

Todd

PS, I did find it tricky to save the custom gamma profile at first but I did
stumble my way through it eventually. I think one of Dan's posts was a bit
more explicit on how to do that than Bruce's if you get stuck.