Low light level color photography

Claim 1

The method of taking color photographs at very low light levels, comprising the steps of: a. focusing the image of the colored subject to be photographed; b. filtering and transmitting said focused image through a filter having, in superimposition and at predetermined angles to each other, filter bars of cyan, magenta, and yellow, respectively; c. collecting, with a field lens, the light transmitted through said filter in order to converge all the light to an image reducing lens; d. reducing, with said image reducing lens, said filtered and transmitted image; e. focusing, with said image reducing lens, said reduced, filtered and transmitted image upon the photocathode input face of an image intensifier tube; f. intensifying the image with said image intensifier tube; g. directing said intensified image from the phosphor output face of said image intensifier tube so as to impinge upon an imaging lens; h. focusing, with said imaging lens, said intensified image upon black and white photographic film; i. developing said black and white photographic film; j. projecting the image of said developed black and white film upon a filter having filter portions of red, green and blue, respectively, in an opaque holder; k. focusing said filtered image on to colored photographic film; l. and, developing and printing said colored photographic film.

Claim 2

The method of taking color photographs at very low light levels, comprising the steps of: a. focusing the image of the colored subject to be photographed; b. filtering and transmitting said focused image through a filter having, in superimposition and at predetermined angles to each other, filter bars of cyan, magenta, and yellow, respectively; c. collecting, with a field lens, the light transmitted through said filter in order to converge all the light to an image reducing lens; d. reducing, with said image reducing lens, said filtered and transmitted image; e. focusing, with said image reducing lens, said reduced, filtered and transmitted image upon the photocathode input face of an image intensifier tube; f. intensifying the image with said image intensifier tube; g. directing said intensified image from the phosphor output face of said image intensifier tube so as to impinge upon an imaging lens; h. focusing, with said imaging lens, said intensified image upon black and white photographic film; i. developing said black and white photographic film; j. projecting the image of said developed black and white film upon a filter having filter portions of red, green and blue, respectively, in an opaque holder; k. focusing said filtered image on to colored photographic film; l. and, developing and printing said colored photographic film.

Claim 3

A system for taking color photographs at very low light levels, comprising: a. means for focusing the image of the colored subject to be photographed; b. a filter, disposed rearward of said focusing means, having line patterns resulting from the superimposition of color filter bars of cyan, magenta and yellow, respectively, at predetermined angles to each other; c. a field lens, disposed rearward of said filter; d. an image reducing lens, disposed rearward of said field lens; e. a three stage image intensifier tube, disposed rearward of said image reducing lens; f. means, disposed rearward of said three stage intensifier tube, for focusing the resultant intensified image upon black and white photographic film, with said film thereafter being developed to form a transparency of the image; g. means for projecting the image formed on the transparency on to color photographic film, with said color photographic film thereafter being developed and printed to form a color photograph; h. and, means, disposed between the black and white film transparency and the color photographic film, for focusing the image formed on the transparency on to means for filtering the transparency image, with said filtering means including an opaque filter holder having radially disposed filter slots of red, green, blue, red, green and blue, respectively, equally spaced from each other.

Claim 4

A system for taking color photographs at very low light levels, comprising: a. means for focusing the image of the colored subject to be photographed; b. a filter, disposed rearward of said focusing means, having line patterns resulting from the superimposition of color filter bars of cyan, magenta and yellow, respectively, at predetermined angles to each other; c. a field lens, disposed rearward of said filter; d. an image reducing lens, disposed rearward of said field lens; e. a three stage image intensifier tube, disposed rearward of said image reducing lens; f. means, disposed rearward of said three stage intensifier tube, for focusing the resultant intensified image upon black and white photographic film, with said film thereafter being developed to form a transparency of the image; g. means for projecting the image formed on the transparency on to color photographic film, with said color photographic film thereafter being developed and printed to form a color photograph; h. and, means, disposed between the black and white film transparency and the color photographic film, for focusing the image formed on the transparency on to means for filtering the transparency image, with said filtering means including an opaque filter holder having radially disposed filter slots of red, green, blue, red, green and blue, respectively, equally spaced from each other.