1) Overexpose for 1/2 or 2/3 steps, so the print looks well in transmitted
light.
2) Develop in non-hardening developer (many brands can be used, I use TETENAL
Eukobrom 1+9).
3) Ordinary *fresh* fixer can be used (I use ILFORD Hypam 1+9).
4) Wash (very) well, as leftover hypo would cause overall hardening during
bleaching.
5) Make up the bleach with destilled water and use purified chemicals, so no
iron ions can interfere with the bleaching process (would also cause overall
hardening).
6) Bleach double the time required for the image to disappear.
7) Wash until the paper looks white again.
8) Fix in fresh (rapid) fixer for 1-2 min.
9) Wash 15 min.
10) Soak in diluted sulfuric acid (1-5%) for 1-5 min. This acid bath is not used
to let the last traces of the image disappear, but to bring up the relief. The
more concentrated the acid and the longer the soaking, the higher the relief
will be. (Never pour water into the acid, but acid into the water!)
11) Wash 5 min. (This water must not be colder than the acid bath.)
12) Contrary to others who let swell the gelatin of the Document Art paper at
ca. 24 degrees C, I prefer water of 40-50 degrees C for 5-10 min.
13) Inking up should be done with the stiffest ink available. I use lithographic
ink like it is used for stone printing first and if the image should be too
contrasty I switch to (stiff) offset ink. To ink up as fast as possible, I first
use the foam brayer until half the work is done and then the brush(es). I get
them made from an old german manufacturer, who makes them the same way as they
did it 60 years ago...
I do not know wether this has been published here allready: spraying a mist of
water over the image with a sprayer used to moisten flowers works well with the
Doc Art paper to give it more contrast after prolonged inking time, if you do
not want to resoak in water again. Brightening small areas can be achieved by
pressing a moist piece of blotting paper, soaked in water with a little ammonia
in it, on that area and overworking it with the brush or brayer.
Klaus Pollmeier