Process for composite photography

• US 4,417,791 A
• Filed: 08/19/1982
• Issued: 11/29/1983
• Est. Priority Date: 08/19/1982
• Status: Expired due to Term

• Current Assignee: Jonathan M. Erland
• Original Assignee: Jonathan Erland, Roger Dorney
• Inventors: Erland, Jonathan, Dorney, Roger
• Primary Examiner(s): Hayes, Monroe H.
• Application Number:
  US06/409,749
• Time in Patent Office: 467 Days
• Field of Search: 352/45, 352/46, 352/47, 352/48, 352/85, 352/87, 352/89, 352/49, 352/44
• US Class Current: 352/45
• CPC Class Codes: G03B 15/08 Trick photography

Abstract

A reverse blue screen process for travelling matte cinematography, which comprises the formation of travelling mattes by pre-coating models or other foreground subjects utilized in composite cinematography with one or more phosphor materials which are invisible upon exposure to visible light, but which emit light of predetermined wavelengths upon excitation by ultraviolet light, and exposing the models through appropriate filters to produce mattes of the predetermined portions of the models coated with the phosphorescing materials, by thus reversing the conventional blue screen process for travelling matte cinematography and exposing an illuminating foreground subject against an opaque background rather than an opaque foreground subject against an illuminated background, it is possible for the first time to successfully matte finely detailed models or other foreground subjects displaying specular reflectance in a single film process.

Claims

1. In a travelling matte process for composite photography, which comprises exposing a photosensitive medium to a foreground subject in front of a contrasting backing, printing high contrast black-and-white mattes therefrom, and printing images of the foreground subject in registration with said mattes and with a predetermined background scene to produce composite photographic images;

the improvement comprising luminescing at least portions of the foreground subject during the exposure step at wavelengths actinic to said medium to form an image of solely said portions of the foreground subject in said medium, and printing said mattes from said image.

2. The travelling matte process of claim 1, wherein the foreground subject is pre-coated in at least said portions with at least a phosphor material which is invisible upon exposure to visible light, but which emits light of predetermined wavelengths upon excitation by ultraviolet light, and wherein the foreground subject is illuminated by ultraviolet light, said portions of the foreground subject thereby phosphorescing and forming said image.

3. The travelling matte process of claim 2, wherein the photosensitive medium is exposed to the light emitted by the phosphorescing portions of the foreground subject through filter means which filters out ultraviolet light and substantially all visible light other than that of said predetermined wavelengths in order that said image is formed solely by said portions of the foreground subject.

4. A reverse blue screen process for travelling matte cinematography, which comprises:

(a) printing color images of a foreground subject and a background scene with visible light on color negative films;

(b) exposing a color negative film to the foreground subject by illuminating the foreground subject with ultraviolet light and luminescing at least portions of the foreground subject at wavelengths actinic to said film to form a matte negative of solely said foreground subject in the film, the ultraviolet light exposure being synchronized with the visible light exposure of the foreground subject in step (a) to facilitate subsequent registration of the images formed thereby;

(c) reversing the matte negative formed in step (b) and printing a high contrast black-and-white burn-in matte therefrom;

(d) reversing the burn-in matte to produce a high contrast black-and-white hold-out matte therefrom; and

(e) compositing the burn-in and hold-out mattes with the color images of the foreground subject and background scene formed in step (a) to produce the desired composite color image thereof.

5. The reverse blue screen process of claim 4, wherein the foreground subject is pre-coated in at least said portions with at least a phosphor material which is invisible upon exposure to visible light but which emits blue light upon excitation by ultraviolet light, and wherein said portions of the foreground subject phosphoresce upon the ultraviolet light illumination thereby forming said matte negative.

6. The reverse blue screen process of claim 4, wherein the foreground subject is pre-coated in predetermined areas with at least two phosphor materials which are invisible upon exposure to visible light but which emit light at distinct wavelengths upon excitation by ultraviolet light, and wherein high contrast black and white mattes are sequentially formed of said predetermined areas of the foreground subject to permit compositing of each of said areas with the background scene.

7. The reverse blue screen process of claim 4, wherein the color images printed in step (a) are formed by exposing a foreground subject and a background scene to visible light to form color negatives thereof, and said negatives are thereafter reversed to form corresponding interpositives, wherein the burn-in and hold-out mattes are composited in step (e) with the interpositives of the foreground subject and the background scene, respectively, to produce a composite color dupe negative, and wherein the color dupe negative is reversed to produce the desired, composite color print.

8. A reverse blue screen process for travelling matte cinematography, which comprises:

(a) coating predetermined portions of a finely detailed model, displaying specular reflectance and comprising a foreground subject, with phosphor materials which are invisible upon exposure to visible light but which emit blue, red and green light, respectively, upon excitation by ultraviolet light;

(b) exposing a color negative film to the model in visible light to form a color negative thereof;

(c) in synchronism with step (b), exposing said film to the model through a blue filter and illuminating the model with ultraviolet light to form a matte negative of the blue-phosphorescing areas of the model on said film;

(d) further in synchronism with step (b), exposing said film to the model through a red filter and illuminating the model with ultraviolet light to form a matte negative of the red-phosphorescing areas of the model on said film;

(e) further in synchronism with step (b), exposing said film to the model through a green filter and illuminating the model with ultraviolet light to form a matte negative of the green-phosphorescing areas of the model on said film;

(f) exposing a color negative film to a background scene in visible light to form a color negative thereof;

(g) reversing the color negatives of the model and the background scene to form interpositives thereof;

(h) printing high contrast black-and-white mattes from each of the matte negatives formed in steps (c), (d) and (e); and

(i) compositing the interpositives formed of the model and the background scene in steps (b) and (f) with the black-and-white mattes of the blue-, red- and green-phosphorescing areas of the model, and printing composite color images thereof.

9. In a travelling matte process for composite photography, which comprises exposing a photosensitive medium to a foreground subject in front of a contrasting background field, printing high contrast black-and-white mattes therefrom, and printing images of the foreground subject in registration with a predetermined background scene and said mattes to produce composite photographic images;

the improvement comprising luminescing at least portions of the foreground subject or the background field at wavelengths actinic to said medium to form images of solely said portions of the foreground subject or background field in said medium, and printing said mattes from said images.