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10.08.2017 PWT 32-2017 The Rise and Decline of the Aristotype Process

 

The term aristotype derives from the Greek ἄριστος (aristos) « excellent, » and τύπος (typos), impression. So the best way to print a photographic image. The name ‘aristotype’ was used indifferently for both gelatin and collodion base photographic coated paper.

Between the era of albumen (1850s-1890s) and the era of silver prints (1920s-1998s), aristotypes were very popular, neighboring pictorialist sophisticated processes as well as Kodak cameras. It is considered a very easy process for amateurs, avoiding many manipulations:

“There are many advantages: a greater sensitivity, a consistent quality, ease of treatment (fixing-toning in one bath) a glossy surface, and good resolution. Their prepared coating made them the precursors of 20th century photographic papers…”

 

Intensively used during twenty years (1895-1914), they disappeared during WWI. One reason of the decline is that aristotypes are contact prints …

… they have the same size as the negatives and are easily viewed, mostly 9 × 12 cm up to 30×40 cm (those large flowers). This is not possible with small 24×35 mm negatives. When the photographers had to enlarge the negatives, they decided to use development paper.

“From a technological point of view, the great innovation of aristotypes resides first of all in the use of an emulsion.

The sensibilisation of the base is no longer done by successive soakings but by coating with a solution containing suspended photosensitive salts. The paper support is subject to a treatment; baryta coating. This method, patented in 1881, by Hutinet and Lamy and designed to give a glossy surface to the photograph, consists in giving to the paper a coating of barium sulfat in suspension in a gelatin, arabic gum or albumin solution. Gelatin is the most commonly used binder. With the time the formulation evolved and manufacturers introduce wax, casein, milk, starch…etc.

The first aristotypes were hand coated, the emulsion being poured on a sheet of paper already fixed in a frame or fixed by three angles on a wood plate. However, very soon, the coating was automated using a cylinder machine…
After exposure, the samples are washed, toned with gold or platinum, then fixed (After 1914, the price of these metals increased dramatically).

The fixing bath removed the residual silver salts. When the sample is immersed, a fading and change of tone can be observed. These two phenomena, which do not occur with development paper, have several physical and chemical origins. The color shift is due to the transformation of the silver colloidal-chloride complex into silver gelatin (or collodion) whose maximum absorption is situated at a short wavelength. The dissolving of the silver chloride leaves space in the binder where the silver particles can rearrange themselves and coagulate, which modifies their optical qualities.

As soon as they were produced aristotypes were announced as permanent processes. They are, it is true, much more stable than the albumen papers but … their stability is due mainly to the way in which the images are treated, handled and stored.

Collodion aristotypes are mechanically fragile; they scratch easily and the image layer can sometimes leave the support.” (Cf. Bertrand Lavedrine, online : ).

http://resources.conservation-us.org/pmgtopics/1991-volume-four/04_08_Lavedrine.html
 

PWT 32-2017 Aristotype Flowers

 

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