[AV Media Matters] Photoshop working space settings for grayscale images

[kiwi1@alaska.net]

Hi everyone

I have a question for the expert Photoshop users in the group.  I am
working on a newspaper photograph digitization project with a small
regional library in Alaska and trying hard to get up to speed with
issues such as calibration, and determining appropriate Photoshop
settings for greyscale scans (I am a librarian not a scanning
expert!).

We are scanning a collection of 5,000 photographs, the majority of
which are Black & White.  We are using Photoshop 6.0. on a PC, with
Windows 2000 professional version and an Epson 836 XL flatbed
scanner.  We use Expson Scan II32 and TWAIN 1.75 pro to determine
our scan settings.  We are scanning the images at 12 bit grayscale
at a resolution of ~4,000 pixels along the long side of the image.
We are scanning at a high resolution and bit depth for archival
purposes,so that the digital image can be output to both an ordinary
ink jet printer,and on a high end printer.

The question we have has to do with determining which working space
setting we should use for our gray scale scans in Photoshop 6.0.
The default gray scale setting is selected from the Color Settings
Dialog box.  Should the Gray working space be Gamma 2.2 or Dot Gain
20% or some other setting?  We found that we when we used the "Dot
Gain 20%" setting the image on thescreen more closely resembled the
source photograph than the Gamma 2.2 setting.  We calibrated our
monitor using Adobe Gamma, but of course, this is a pretty
subjective evaluation (reliant on the ambient lighting, users
perceptionetc.).

 From the reading I have done, you should choose as the default
setting that which  "most closely matches the behavior of your most
common grayscale output." (Bouton, Gary.  Inside Adobe Photoshop 6).
However, as described, we have not scanned the image with a specific
device in mind, (although, we DO plan to purchase an Epson 2000
printer so that we can make in house copies of photographs).  The
default working space profile we select in the Color Settings dialog
box applies to newly created files.

In short, we are puzzled and hopeful that someone out there can shed
light on how to determine which setting we should select for gray
scale image.  All input will be much appreciated.

I also pass on this fact (which is obvious now that I think about
it...) that you cannot calibrate your scanner for greyscale output
using a calibration tool such as Monaco EZColor or Agfa Fototune
because they are color calibration tools....so you cannot create a
grayscale profile for your scanner.

thanks for your help.

Judith

Judith A.K. Terpstra
Information Access
6921 Brayton Drive #210
Anchorage, AK 99507
Phone: (907) 349-7478
Fax: (907) 344-7958