AshigrainColour reversal · Experimental
Technicolor Process II
Red and blue-green, cemented back to back.
A two-colour palette of red-orange and blue-green. Original vs Ashigrain.
At a glance
- Exposure index
- 16
- Daylight
- Introduced
- 1922
- Discontinued
- Process
- Technicolor two-colour cemented print (silver removed, records dyed, cemented back to back)
- Prints on
- Reversal, viewed directly
About the film
Technicolor's Process II was the first colour system to carry its colour in the release print itself, so its films could run on any standard projector.
Technicolor had been founded in Boston in 1915 by the engineers Herbert Kalmus, Daniel Comstock and Burton Wescott, and its first, additive process needed special projectors; after its 1917 demonstration film The Gulf Between failed, the company spent five more years on a new camera and printing method. The camera, designed in 1921 by the 27-year-old Joseph Arthur Ball, split the light behind the lens with a prism into red- and green-filtered records on one black-and-white negative. Each record was printed onto its own strip of half-thickness film, which Eastman Kodak developed with Technicolor, and the strips were dyed, the red record green and the green record red, and cemented back to back. With only two colours the process could not show true blues, purples or yellows, so productions planned their colours with care. The Toll of the Sea (1922), the first starring role of the 17-year-old Anna May Wong, was the first feature made this way and a commercial success, and Paramount's all-colour Western Wanderer of the Wasteland followed in 1924. More often, studios used it for colour sequences in black-and-white features such as Ben-Hur and The Merry Widow, but the cemented prints scratched easily and buckled out of focus in the heat of the projector. By the late 1920s Technicolor had moved to single-strip dye-transfer prints made from the same camera negatives, and surviving Process II prints have faded towards orange.
Sources for this history
- Two-Color Process, George Eastman Museum
- Technicolor No. II, Timeline of Historical Film Colors (University of Zurich)
- Dye-Transfer Printing, George Eastman Museum
- [The Black Pirate – Mary Pickford Technicolor No. 2 Test] (US 1926), George Eastman Museum
- 1915–1935, George Eastman Museum
- The Toll of the Sea (1922), National Film Preservation Foundation
- The Toll of the Sea, Internationale Filmfestspiele Berlin
- Technicolor No. III, Timeline of Historical Film Colors (University of Zurich)
- The Black Pirate, Library of Congress, National Film Preservation Board
- A Director Remembers Making the First Color Feature, Hollywood Studio Magazine (Media History Digital Library)
- Hidden treasure in a film can: notes on our Technicolor rediscovery, British Film Institute
Shot on Technicolor Process II
The Toll of the Sea
The first feature made in Process II, released in cemented two-colour prints that ran on standard projectors.
Wanderer of the Wasteland
Paramount's all-colour Western, photographed by Arthur Ball in Technicolor's cemented process.
Fig Leaves
Partly: two colour sequences, printed in Technicolor's cemented process.
The look
Technicolor's Process II was a 1920s two-colour system whose prints were cemented back to back. Two records, dyed red-orange and blue-green, give a palette of reds, oranges and blue-greens; true blues drift to blue-green and yellows to orange.
Blues turn blue-green in a two-colour palette.
Skin and reds in two colours.
Best for
- Sunlit gardens, flowers and foliage
- Silent-era pastiche and period drama
- Stylised costume and fashion scenes
Among the films
Science & sources
A two-colour model inspired by the system, not a reproduction of Process II. Every curve is generated from named assumptions, guided by museum descriptions of the process.
Response curves and the evidence behind the model
Compare manufacturer data with the Ashigrain model on the same axes. This shows the calibration to source curves; comparison with photographed film is a separate question.
Characteristic response
RMS granularity
Density variation (σD). Where the datasheet gives a single grain value, the response away from that point is an approximation.
| Channel | Density | Datasheet-based σD | Model σD |
|---|---|---|---|
| R | 0.3 | 0.007803 | 0.008117 |
| G | 0.3 | 0.005515 | 0.005749 |
| B | 0.3 | 0.009648 | 0.010176 |
| R | 0.6 | 0.014313 | 0.014889 |
| G | 0.6 | 0.01121 | 0.011686 |
| B | 0.6 | 0.022259 | 0.023478 |
| R | 1 | 0.02296 | 0.023884 |
| G | 1 | 0.019274 | 0.020092 |
| B | 1 | 0.038135 | 0.040223 |
| R | 1.5 | 0.029592 | 0.030783 |
| G | 1.5 | 0.028175 | 0.02937 |
| B | 1.5 | 0.059435 | 0.06269 |
| R | 2 | 0.030736 | 0.031973 |
| G | 2 | 0.033158 | 0.034565 |
Model limits
These images show the film model in use. Spectral response, lighting and viewing conditions include approximations, while halation, bloom, grain size, weave and flicker are not fully measured for each film. A real film capture also depends on development and print timing.
- Technicolor Process II is a labelled surrogate: a two-colour model inspired by the system, not a reproduction of Process II.
- No characteristic curve, spectral sensitivity, dye spectrum, MTF or grain measurement of Process II exists in the sources. Every curve is generated from named assumptions, guided by qualitative museum descriptions.
- The model runs the two records in a three-layer path: the blue layer copies the green record and there is no yellow dye.
- The exposure index of 16, the daylight balance and the 35 mm format are assumptions.
- MTF is proxied from Kodak Vision3 50D (5203) and grain from Kodak Ektachrome 100D (5294).
- Custom lighting spectra, camera metering and the spectral reflectance inferred from fixed-white-balance footage are modeled assumptions, not measurements of this film.
- Push and pull have no published curves for this film and use a generic model.
- Characteristic response outside the published exposure range is an extrapolation, not measured film data.
- Veiling projection flare is not measured in the available sources. Its modeled contribution lifts screen blacks; it is not a measured projection-contrast claim.
Film guide: assumptions and practical choices
Sources
- Process: George Eastman Museum: Technicolor, Two-Color Process, Wayback capture 20260308185320 of www.eastman.org/technicolor/technology/two-color-process, p. 1
- Reconstructed: George Eastman Museum: Technicolor, Two-Color Process, Wayback capture 20260308185320 of www.eastman.org/technicolor/technology/two-color-process, p. 1