Digital BW, The Print

Hello Pieris,

>Apparently there wasn't one before, or it's not readily available.
>
>Because this is my first attempt at profiling and I prefer not to
>work in isolation, I'd appreciate feedback on this curve. It should
>provide superior tonal separation in midtones and deep blacks.

After quite extensive experimenting with BO printing I found that
canned curves aren't necessary for BO, and in fact are largely
ineffective in the sense that a curve worked out for one image is
usually not appropriate for another.  Any fixed curve that is applied
universally to every image will likely be a compromise in some way. 
That's why you don't find any BO curves published anywhere.

The reason for this is that curves/profiles are needed with ink
systems that blend multiple inks because they are controlling the
places where the different inks cut in and out.  Since different
papers react differently to the inks, a different curve is needed for
each ink/paper combination.  

With BO printing only one ink is used so the problem of partitioning
doesn't exist.  The basic workflow is to use a common paper for all
proofing, such as EEM, and work up an image to its best appearance
(using levels, curves, whatever) on that paper, and then save the
image. This image will always look its best on EEM as is, and the
proof then serves as the model for final prints on fine art papers.

For final prints, depending on the paper used, a contrast curve may be
needed to adjust the image to match the proof, because the different
papers have different contrasts, very much like silver gelatin papers.
 This curve will usually be different for each paper, and a curve for
an image on Condor BW, for example, will most likely not be
appropriate for a different image on that paper.  So even these
paper-specific contrast curves can't be applied to every image.  These
curves are usually quick and easy to create, and can be saved either
as an adjustment layer in the image or in a curves file (I use the
former method, even though it adds to file size, because it's more
convenient).

This is one reason why BO printing is so easy - we don't need canned
curves and aren't dependent on someone with a densitometer or other
form of expertise to provide them.  There's more to good BO printing
than just the curves, of course.  A more detailed explanation is found
in a series of articles at the link below.

Regards,
Clayton


Info on black and white digital printing at    
http://www.cjcom.net/digiprnarts.htm