A three colour subtractive reversal print stock. It appeared in 1934 and was
the first three layer colour film that could be processed with minor
modifications to contemporary laboratory techniques. It did not
require toning, colour development or use of dyes during processing. It
used pre-dyed emulsions and dye bleaching.
An illustrated description of the way the processed worked is available as a pdf file.
GASPARCOLOR.pdf
Bela Gaspar who invented this system had a number of patents to his
credit:
GB415040: GB446392: GB480854: GB483366
The film had to be shot as three colour separations. Here is a
test film and a digital reconstruction of three of the frames:
It seems as if sound tracks could be of various colours; also
variable area and variable density, here are some samples:
These are sample frames from a Gasparcolor film..
Please feel free to contact me if the description is not clear or you have
further questions. Email me at Brianrpritchard@aol.com