PATENT TALK
A. Method for
Color Cinematography- US 1359024[1] dated 16
November 1920
This particular invention was
patented in the year 1920 when most of the film industries were producing films
in Black and White. There was a necessity to invent a method to produce movies
in color. The patent was filed on 27 December 1919 by Brewster
Percy Douglas, an American inventor.
At that time color movies were
produced using the following method as cited by the inventor as a prior art[2].
“Series of images or pictures on one
of the films taken through a red filter and the other series on the other film
taken through a green filter; and then by contact to print the two series on
the opposite sides of a positive film which is sensitized on both sides. The
positive film is then developed and fixed, and the images on the two sides are
stained or colored, say red on one side and green on the other, so that when
the two images are projected (of course simultaneously) on the screen a unitary
image in substantially natural colors will result.”
The inventor further identified
the problem in the prior art and describes the same as follows[3]:
“So far as I am aware this
method, in which the color records are made on two separate films has never
been successful in practice, however attractive in theory; the reason being the
difficulty, insuperable, of securing accurate enough registry of the
images in printing them on the positive film. The necessity for accurate
registry will be apparent when it is remembered that if the pictures are out of
registry on the positive film the defect, greatly magnified, is evidenced on
the screen by red and green color bands or fringes at the edges of the objects
photographed.”
Further he describes his
invention which is an improved method of color cinematography as follows[4]:
“In carrying out the invention in
the preferred manner a pair of light images of the object to be photographed
are projected to separate focal plane areas; two perforated negative films are
passed step by step through the respective focal plane areas to bring the
successive image or picture spaces to the exposure positions and the films are
so positioned that at least one selected perforation in each film is in a
certain definite and exact relation to the respective light image, this
relation being constant through out the series of steps; and the films are
exposed to the light images while in such positions. Then the negative images
produced on one film have with respect to.
Opposite sides of the positive
film, if the perforations in the latter are registered with the perforations in
the two negative films, the resulting positive images will be in accurate
registry, and when projected will produce a single or unitary image on the
screen. The positioning of the negative films in their respective focal plane areas
is effected by the use of registry pins, which enter the selected perforations,
say one on each side of the film, before the exposure is made, so that if a
picture-space on the film has at any step been brought to only an approximately
correct exposure position the pins will shift the film in one or more
directions, in its own plane, to bring the picture-space exactly to the
exposure position.
Usually the same perforations as
were used to locate the negative images are then used to register the negative
images with negative film.”
The inventor highlights the
following as the spirit of his invention.
¥ He used two
lenses, one for each film, instead of a single lens.
¥ Two
exposures (to make an image pair or group) may be made one after the other
instead of simultaneously.
¥ In place
of exposing two negative films a single film of double width may be used and
the images made side by side, After exposure the negative can be split
lengthwise to form two separated color records, if desired, or its images can
be printed on the two sides of the positive without splitting the negative in
two.
¥ For
three-color cinematography three separate negative films may be used.
Brewster was a series inventor in
the cinematography field. He was granted many patents both in USA and abroad.
Brewster was the first to shoot a color photograph of President Wilson[5]. The color cinematography produced by using his
inventions is popularly known as Brewster Color. The one-shot Debut of Thomas
Cat (general release Feb. 20, 1920) was for many years regarded as the first
color cartoon to have been widely distributed[6]. The
film was processed by Brewster Color.
[1]http://pdfpiw.uspto.gov/.piw?docid=01359024&SectionNum=3&IDKey=8C9E15FCAC2C&HomeUrl=http://patft.uspto.gov/netacgi/nph-Parser?Sect2=PTO1%2526Sect2=HITOFF%2526p=1%2526u=/netahtml/PTO/search-bool.html%2526r=1%2526f=G%2526l=50%2526d=PALL%2526S1=1359024.PN.%2526OS=PN/1359024%2526RS=PN/1359024
[2] US Patent No.1359024
[3] US Patent No.1359024
[4] US Patent No.1359024
[6] http://brayanimation.weebly.com/other-series.html
