The presentation discusses possibilities and limitations in the employment of XRF towards identification of both major German two-colour processes, Siriusverfahren and Ufacolor. In film archives, an odd lack of vintage prints identified as either of these early colour processes from the 1920s and 30s is evident. This ‚absence’ of an important part of German colour film heritage can be attributed to insecurities in visual attribution, but mainly to generally low survival rates of advertising films, missing title sequences, incomplete filmographies and cataloguing, low survival rate of contextual sources, lack of scholarly and archival attention. Occasionally, strikingly brilliant films or fragments evidencing a two-colour process surface in archival collections. These prints with emulsion on both sides, and applied colour toning – on one side blue-green the other red-orange – can be result of the Agfa-Bipack process, termed Ufacolor, or the Sirius process invented and marketed by Ludwig Horst and his sons. The presentation explores how laboratory analytics can help towards ID of the colour process employed in producing the film, also in defining the aim of digital restoration. It shall discuss which (combination of) elements can serve as markers for each two-colour process, offsetting these against less helpful elements, which frequently occur from other causes in film stock manufacture, processing and ageing.
To be screened: MELODIE DER WELLEN (D 1931) s/w mit 2-Farben Sequenz rot-blau: Sirius Verfahren (?), Ni Pos, 70m, 3min DIE FLAMME (D 1933) 2-Farben rot-blau + gelb: Ufacolor Verfahren, Ni Pos, 42m, 2min IN SPANIEN (D 193?) 2-Farben rot-blau + gelb: Ufacolor Verfahren (?), Ni Pos, 15m, 1min
Mordants, Microscopy, Spectroscopy: Studying and Identifying Early Color Systems
Sreya Chatterjee, Caroline Figueroa Fuentes, Ulrich Ruedel HTW - University of Applied Sciences, Berlin
Subtractive bi-pack two-colour systems employing both metal and dye toning were widely experimented with in 1930s in the quest of simulating natural colour tones in films. Despite the obvious limitations, these two-colour systems were able to create a semblance of skin tones as well as a curious gamut of colous on the screen, which was employed, for instance, in a number of animated films from that era. Selected two-colour systems, which were prevalent between 1920s and 1940s, namely Ufacolor, Sirius, Multicolor and Cinecolor have been studied microscopically and through instrumental-analytical chemistry with the aim of scrutinising their visual characteristics and chemical makeup in terms of their mordant constituents. In this presentation, the results of these comparative investigations of these samples will be presented, observed macroscopically as well as through transmission microscopy, alongside their chemical characteristics as revealed through Fourier-transform Infrared Spectroscopy (FTIR) and X-ray Fluorescence (XRF) analysis.
