Van Dyke Brown printing

VanDyke printing was on my list of the 19^th century ‘techniques to try’ for a long time.  While working with cyanotypes, collodion and other techniques I had most of the chemicals needed for VDB handy and the only new ingredient I had to buy was a tartaric acid (easly accessible, for example, on ebay).

VanDyke Brown process is based on iron (iron ferrous citrate) and  is one of the POP techniques, similarly like cyanotype, platinum or palladium. VanDykes have a wide tonality range compared with pl/pd prints, when printed with the right negative, but the process is cheaper and less complicated.  
As Sarah van Keuren explains in her book 'A non silver manual', Van Dykes (along with pl/pd) have self-masking characteristics - shadow areas turn reddish brown during the exposure, acting as a filter. It allows for longer exposure of hightlights without losing details in the shadows. (It doesn't happen with cyanotype)
Kallitypes (similar process, but using ferrous oxalate) and Van Dykes are often called 'the poor man's platinum prints'.

VDB Receipt:

Ferric ammonium citrate 9g
distilled water 33ml

tartaric acid 1.5g
distilled water 33ml

silver nitrate 3.8g
distilled water 33ml

/mix 3 parts together/

I processed my van dykes in water with an addition of a pinch of citric acid (5 min bath) plus ca 2min in running water, and fixed with 3% hypo fixer. Washed for 30 min after all.

I experimented a bit with different negatives, single and double coating and papers. 

The main issue stays, of course, a proper negative. In my first tries I realised it’s not easy to get a good print from original B&W negative (I think it’s easier with cyanotype) and decided to stick to digitally printed transparencies for a moment. From the papers, I had, I like the results with Fabriano Artistico the most. Double coating makes the browns stronger, but  for some  reason I prefer single coating prints. (I'm also having problems with second coating streaks visible) Didn't use any contrasting agent so far.

Scanning doesn't really make them a justice as it exagerates the structure of the paper,(I'm struggling with this for a while - not sure how to scan papers like that), but here are the first prints that I'm quite happy with:

Fabriano Artistico, 400W halogen lamp, 30min exposure (one coating)