I have been unable to determine at what point “brown print” and “Vandyke” became synonymous. The brown print process of Arndt and Troost. The process, which was used primarily for copying maps, bears no relation to Was a photo-lithographic process wherein zinc plates were coated with an enamel consisting of fish-glue, ammonium dichromate, and chromic acid. Cassell’s Cyclopaedia lists it under “kallitype” and refers to it variously as a “modified kallitype” or “water-developing kallitype.” The “Vandyke” process described in early 20th century photographic literature (see Cassell’s and Photographic Facts and Formulas) Well into the 1930’s, the process was referred to variouslyĪs “brown print,” “sepia print,” and sometimes “Kallitype,” but never Vandyke. Schramm did not test some of the more obscure early formulae provided by Dick Stevens in his definitive work Making Kallitypes.ĭespite the fact that “Vandyke” has become established as the name for the brown print process, it is a misnomer. When Bob Schramm tested four different VDB formulas, including the oxalic acid formula, he concluded that the standard formula produced the best results. Since iron hydroxide is very difficult to remove, its formation is prevented by washing in a slightly acidic bath (a pinch of citric acid being added to the tray of water). The downside of this is that an alkaline environment can cause the formation of iron hydroxide. The oxalic acid formula substitutes oxalic for tartaric acid, but requires an alkaline solution to develop. The very similar formula from Cassell’s Cyclopaedia of Photography (1911) recommends mixing just prior to use, whereas the usual recommendation today would be to mix A, B, and C and let the solution ripen for a day or more, then add the mixture to warm gelatine. Gelatin is often omitted, since so many modern papers are already sized. Today’s “standard” brown print formula adheres closely to the original formula patented by Arndt and Troost in 1895, and is found in a multitude of minor variations. Some formulae contain both chemicals, however kallitypes generally require a developer whereas brown print is a Sepia prints, or Vandyke Brown (VDB) and prints from the latter are generally referred to as kallitypes. Prints from the former are generally referred to as brown prints, Ferric-silver processes fall into two broad categories-those which contain ferric ammonium citrate and those which contain ferric oxalate.
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