RE: calling all photoshop gurus

Scott,
 
I just noticed you are using dye based inks, ignore my previous e-mail
as they only apply to quadtone/hextone inks. My bad!
 
Happy Yule,
 
Don
 
 
-----Original Message-----
From: Scott Wainer [mailto:smwbmp@starpower.net]
Sent: Tuesday, December 23, 2003 8:23 PM
To: alt-photo-process-l@sask.usask.ca
Subject: calling all photoshop gurus
 
Happy holidays to all,
 
Is there a way, in photoshop, to set a particular RGB tone (say 20, 20,
20) for shadows and another (say 220, 220, 220) for highlights and, in
doing so, compress/expand the mid-tones to fit within those limits?
 
The reason behind this question is that for the past several years I
have been trying, on and off, to make digital negatives for contact
printing with out much success. I find that my inkjet negatives are
either too contrasty or too flat for the processes I use. Last night I
got the idea of making the negatives fit the process using conventional
densitometry logic (increase exposure for shadow detail and decrease
development for highlight control). So, I created a 256 tone grayscale
stepwedge to test my idea. I chose to limit my tests to a particular
media (Westjet film), a particular printer (Epson 1280), and a
particular ink set (MIS dye inks). I printed four copies of the
stepwedge as follows:
 
1 - 1440 dpi printer resolution (back light film), 480 dpi file
resolution, 6 inks to make black
2 - 1440 dpi printer resolution (back light film), 480 dpi file
resolution, black ink only
3 - 1440 dpi printer resolution (back light film), 240 dpi file
resolution, 6 inks to make black
4 - 1440 dpi printer resolution (back light film), 240 dpi file
resolution, black ink only
 
I then proceeded to take a densitometer reading for each step on each
stepwedge and record the readings. (BTW, I found a maximum density of
2.86 with print 1.)
 
My theroy, being applied to a negative image, is that if I knew the tone
of a particular shadow density (say 0.20 above media) and a particular
highlight density (say 2.00 above media), resulting in a density range
of 1.80, then I could then adjust the tones of the shadows and
highlights of my image to fit a process requiring a density range of
1.80. Which returns me to my question of how to set the shadow and
highlight tones.
 
As an aside, I found that print 4 (contacted with cyanotype) gave the
smoothest gradation and the sharpest look.
 
Any help would be greatly appreciated,
 
Scott Wainer
smwbmp@starpower.net
 
 
Received on Wed Dec 24 00:31:03 2003