[alt-photo] Re: New Platinum Prints

[etienne garbaux]

Davidh wrote:

>This is something that's been concerning me lately. I've been
>preparing my negs for palladium digitally using Mike Wares method. The
>reason for this is that my printer (Epson 1400) won't allow me to use
>any other method as the inks are not very dense. I manage to get
>satisfactory gum prints but I'm thinking I could be missing out on
>something in my palladium experiments. My exposure time using BL tubes
>is 60 seconds. The prints look ok but nothing special. Could this lack
>of negative density have something to do with the way they look? If so
>why?

Be aware that I'm not familiar with Mike Ware's method (although I 
have seen prints attributed to it) and I do not use digital negatives.

There are two things at work here: (i) matching the negative density 
range ("DR") to the printing exposure scale ("ES"); and (ii) the 
character of the exposure scale, however long or short it is.  If the 
DR of your negs is too short to match the printing ES, you'll get 
low-contrast prints with murky (but not very deep) shadows and/or 
fogged-looking highlights.  But even if the negs have the right DR 
for the process, the characteristic curve of the printing process may 
be ugly.

The standard long-scale Pt process has a very, very long linear scale 
with symmetrical, gently rounded toe and shoulder, typically printing 
the whole step wedge with some scale left over.  Therefore, you need 
to use negatives with a very high DR to obtain all of the available 
print zones with this process.  Photographers have not typically made 
negatives this "bulletproof" since the late 19th Century, so folks 
have tried a number of different methods to shorten the Pt exposure 
scale (adding dichromates, hydrogen peroxide, etc., etc.).  These 
tricks shorten the exposure scale by raising the threshold exposure 
-- not really a very promising way to go about it.  Anybody who has 
done serious sensitometry with the process has seen the ugly 
characteristic curves the short-scale versions of the Pt process 
produce.  I have yet to see prints made using any short-scale Pt 
process that came close to the look of "real" (long-scale) Pt 
prints.  Unfortunately, so many workers are using the short-scale 
processes now that many people don't even know what a good Pt print 
is supposed to look like.

I commend to you an experiment:  Make some in-camera negatives with a 
DR above 2.1 (try to hit 2.4 for starters), and print them using the 
standard full-scale Pt process.  I bet you never go back to digi-neg 
Pt printing again, and depending on how big you think prints need to 
be, that you acquire one or more LARGE format cameras or learn to 
make good enlarged negatives in the darkroom (not so easy now that 
slow, blue-sensitive copy films are long gone).  If you have no 
option besides digital, have a service bureau make some 2.4 DR 
negatives with an imagesetter using your files.

Best regards,

etienne