System for varying light intensity such as for use in motion picture photography

An apparatus for providing variable intensity light comprising

• a light source;
• an outgoing aperture;
• a reflector positioned adjacent the light source directing light from the light source along an outgoing light path through the outgoing aperture;
• a primary filter having a portion aligned in the outgoing light path, the primary filter comprising a neutral density section having portions of different densities, the primary filter being movable to locate a selected portion of the filter in the outgoing light path;
• a blocking shroud selectively movable into position in the outgoing light path,
• wherein the neutral density filter comprises a rotatable circular disk positioned in a plane generally perpendicular to the outgoing light path, the circular disk having (a) a clear arcuate section and (b) a variable density arcuate section,
• wherein the circular disk is mounted on a shaft, and wherein the blocking shroud comprises an arcuate section mounted on the shaft, the arcuate section of the blocking shroud being rotatable into a position in the outgoing light path to completely block off any light from passing through the outgoing aperture.

A variable intensity light for motion picture photography, comprising

• a frame;
• a light source supported by the frame;
• a rectangular outgoing aperture;
• a reflector mounted to the frame and positioned adjacent the light source directing light from the light source along an outgoing light path through the outgoing aperture;
• a primary filter having a portion aligned in the outgoing light path, the primary filter comprising a neutral density section having a density which increases from a given low density at a first side of the neutral density section to a selected higher density at second side of the neutral density section, the primary filter being movable via an actuator to locate a selected portion of the filter in the outgoing light path;
• a blocking shroud selectively movable into position in the outgoing light path, wherein the blocking shroud is operably movable via said actuator by which the primary filter is moved.

A movie camera system having a camera housing with a picture recording mechanism, a lens system including a lens focusing mechanism, and a lighting system, the lighting system comprising

• a light source;
• an outgoing aperture;
• a reflector positioned adjacent the light source directing light from the light source along an outgoing light path through the outgoing aperture;
• a primary filter having a portion aligned in the outgoing light path, the primary filter comprising a neutral density section having a density which increases from a given density at a first side of the neutral density section to a selected higher density at second side of the neutral density section, the primary filter being movable via an actuator to locate a selected portion of the filter in the outgoing light path;
• a blocking shroud selectively movable into position in the outgoing light path, wherein the blocking shroud is operably movable via said actuator by which the primary filter is moved;
• and
• a diffuser positioned in the outgoing light path downstream of the primary filter.

A movie camera system having a camera housing with a picture recording mechanism, a lens system including a lens focusing mechanism, and a lighting system, the lighting system comprising

• a light source;
• an outgoing aperture;
• a reflector positioned adjacent the light source directing light from the light source along an outgoing light path through the outgoing aperture;
• a primary filter having a portion aligned in the outgoing light path, the primary filter comprising a neutral density section which increases from a given density at a first side of the neutral density section to a selected higher density at a second side of the neutral density section, the primary filter being movable to locate a selected portion of the filter in the outgoing light path;
• a blocking shroud selectively movable into position in the outgoing light path;
• and
• a diffuser positioned in the outgoing light path downstream of the primary filter,
• wherein the primary filter comprises a circular disk rotatably mounted on a shaft and positioned in a plane generally perpendicular to the outgoing light path, the circular disk having (a) a clear first arcuate section and (b) a second arcuate section comprising the neutral density section;
• wherein the blocking shroud comprises an arcuate section mounted on the shaft, the arcuate section of the blocking shroud being rotatable into a position in the outgoing light path to completely block off the outgoing aperture.

A method of varying the intensity of light from a light source for use in motion picture photography comprising the steps of:

• generating light from a light source;
• directing light from the light source along an outgoing light path and through a section of a movable filter, the movable filter having sections of different light transmission properties;
• varying the light intensity by moving the filter to selectively position in the outgoing light path a section of the filter having a desired density;
• selectively blocking off the light entirely by moving a douser of opaque material in the outgoing light path, the douser and the filter being movable by a common actuating mechanism.