Digital BW, The Print

Todd,

Basically all Silverfast is doing is a mathematical adjustment to the 
raw data and I don't see any reason why it could not be done a number 
of ways in Photoshop or other software.

Now if you really could adjust the brightness of the lamp and/or the 
sensitivity of the CCD array, it would be another story.

Bruce's suggestion sounds workable for the problem we discussed. 
Namely you wind up with a raw scan of 12 or 14 bits of data mapped 
into a 16-bit space but off to one end. Moving it to center in 16-bit 
shouldn't be that difficult.

I need to play with the scanner and software quite a bit more before 
I know it has (or may not have) to offer. A lot of it may just be 
ease of use and speed. I am afraid I just don't know enough about it 
to give you a good answer. Maybe George would jump in here. I know he 
uses it and has lots of experience with it.

Martin

--- In DigitalBlackandWhiteThePrint@y..., Todd Flashner <tflash@e...> 
wrote:
> 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.