Digital BW, The Print

Hello Alan,

>The question is: For =good= BW printwork, should the final image sent
>to the printer be a TRUE, single-channel grayscale image, with no RGB
>info? 

I have experimented numerous times over the years comparing BW prints
from RGB vs Grayscale files, using both color ink processes and
dedicated BW ink sets.  There were always slight differences but
nothing that would indicate that a "better" print (in any sense that I
could think of) came from either one.  It really boils down to
differences in workflow.

Some people like to apply split toning and tinting effects, which are
color-based and require RGB files.  In addition, there are software
products that apply special effects, such as grain, BW film emulation
and edge effects, which require RGB files.  I don't use any of those
techniques in my workflow, so for me there are no reasons or
advantages for RGB.

On the other hand, there are attributes of grayscale files which I
consider to be significant advantages.  First, they are 1/3 the size
of RGB.  Besides the smaller enlarged file size during workup, with
multiple layers, selections, masks, etc., it makes a huge difference
in storage space for the final master files permanently saved for
printing.  Second, the various image manipulations done in PS go a lot
quicker on a single channel file.  This can make a significant
difference in the total amount of time one spends working up an image.
Over time, both of these are important issues.

For me it's no contest.  After RAW conversion and color-to-BW
conversion, the next step is 16-bit grayscale where it remains. My
primary workflow now is a 2400 in ABW mode.  Any warm/cool toning is
done with the inks, and it produces beautiful results from grayscale
files.

One other issue worth considering has nothing to do with the prints -
display on a web site.  If your prints are warm tone, for example, and
you want the web image to look like the print, then the web image will
have to be RGB.  But, as David mentioned, it's easy enough to take the
small web site file back to RGB for that purpose.

Regards,
Clayton


Info on black and white digital printing at    
http://www.cjcom.net/digiprnarts.htm
I-Trak 2.1   http://www.cjcom.net/itrak.htm