Soft edge mask

A master soft edge mask for use in the manufacture of soft edge masks for use in turn in the projection of a photographic image on to a viewing screen and which master soft edge mask comprises:

• a panel of photographic material;
• a continuous mask portion formed by a substantially opaque area of said panel and defined by a clearly focussed edge of a first size and having a predetermined shape;
• a continuous clear portion formed by a substantially transparent portion of said panel and defined by a clearly focussed edge of the same said predetermined shape but having a second size different from said first size;
• and
• a margin portion extending between said mask portion and said clear portion, said margin portion having a light transmissability progressively decreasing from said transparent portion to said mask portion and, at all positions between said transparent portion and said mask portion, being clearly focussed and having a shape the same as said predetermined shape but being proportionately sized relative to said first and second sizes and intermediate said first and second sizes, and which master soft edge mask is manufactured by a method which comprises:
• positioning a mask object in front of a photographic camera housing a photographic film;
• illuminating said mask object;
• operating said camera to make a first exposure in turn to provide a clearly focussed photograph of said mask object on a single frame of said photographic film;
• adjusting at least one of said mask object and said camera whereby to alter the size of the image of said mask object on said single frame of film;
• operating said camera to make a second exposure to provide a clearly focussed photograph of said mask object on the same said frame and;
• repeating said steps a predetermined number of times while varying at least one of the illumination of said mask object and the exposure time during said steps to build up a said margin portion comprising a plurality of strips having light transmissabilities varying progressively from almost clear adjacent said clear portion to almost opaque adjacent said mask portion.

A master soft edge mask for use in the manufacture of soft edge masks for use in turn in the projection of a photographic image on to a viewing screen and which master soft edge mask comprises:

• a panel of photographic material;
• a continuous mask portion formed by a substantially opaque area of said panel and defined by a clearly focussed edge of a first size and having a predetermined shape;
• a continuous clear portion formed by a substantially transparent portion of said panel and defined by a clearly focussed edge of the same said predetermined shape but having a second size different from said first size;
• and
• a margin portion extending between said mask portion and said clear portion, said margin portion having a light transmissability continuously and progressively decreasing from said transparent portion to said mask portion and, at all positions between said transparent portion and said mask portion, being clearly focussed and having a shape the same as said predetermined shape but being proportionately sized relative to said first and second sizes and intermediate said first and second sizes, and which master soft edge mask is manufactured by a method which comprises:
• positioning a mask object in front of a photographic camera housing a photographc film;
• illuminating said mask object to provide a clearly focussed image of said mask object on a single frame of said photographic film;
• continuously adjusting at least one of said mask object and said camera whereby to alter the size of said image of said mask object on said single frame of film;
• and
• operating said camera to make a continuous exposure of said mask object on the same said frame during said continuous adjustment while continuously varying at least one of the illumination of said mask obect and the effective exposure time to build up a margin portion having a light transmissability varying continuously from almost clear adjacent said clear portion to almost opaque adjacent said mask portion.

A soft edge mask manufactured as a reproduction of a master soft edge mask and for use in the projection of a photographic image on to a viewing screen and which master soft edge mask comprises:

• a panel of photographic material;
• a continuous mask portion formed by a substantially opaque area of said panel and defined by a clearly focussed edge of a first size and having a predetermined shape;
• a continuous clear portion formed by a substantially transparent portion of said panel and defined by a clearly focussed edge of the same said predetermined shape but having a second size different from said first size;
• and
• a margin portion extending between said mask portion and said clear portion, said margin portion having a light transmissability progressively decreasing from said transparent portion to said mask portion and, at all positions between said transparent portion and said mask portion, being clearly focussed and having a shape the same as said predetermined shape but being proportionately sized relative to said first and second sizes, and intermediate said first and second sizes, and which master soft edge mask is manufactured by a method which comprises:
• positioning a mask object in front of a photographic camera housing a photographc film;
• illuminating said mask object;
• operating said camera to make a first exposure in turn to provide a clearly focussed photograph of said mask object on a single frame of said photographic film;
• adjusting at least one of said mask object and said camera whereby to alter the size of the image of said mask object on said single frame of film;
• operating said camera to make a second exposure to provide a clearly focussed photograph of said mask object on the same said frame and;
• repeating said steps a predetermined number of times while varying at least one of the illumination of said mask object and the exposure time during said steps to build up a said margin portion comprising a plurality of strips having light transmissabilities varying progressively from almost clear adjacent said clear portion to almost opaque adjacent said mask portion.

A soft edge mask manufactured as a reproduction of a master soft edge mask and for use in the projection of a photographic image on to a viewing screen and which master soft edge mask comprises:

• a panel of photographic material;
• a continuous mask portion formed by a substantially opaque area of said panel and defined by a clearly focussed edge of a first size and having a predetermined shape;
• a continuous clear portion formed by a substantially transparent portion of said panel and defined by a clearly focussed edge of the same said predetermined shape but having a second size different from said first size;
• and
• a margin portion extending between said mask portion and said clear portion, said margin portion having a light transmissability continuously and progressively decreasing from said transparent portion to said mask portion and, at all positions between said transparent portion and said mask portion, being clearly focussed and having a shape the same as said predetermined shape but being proportionately sized relative to said first and second sizes and intermediate said first and second sizes, and which master soft edge mask is manufactured by a method which comprises:
• positioning a mask object in front of a photographic camera housing a photographc film;
• illuminating said mask object to provide a clearly focussed image of said mask object on a single frame of said photographic film;
• continuously adjusting at least one of said mask object and said camera whereby to alter the size of said image of said mask object on said single frame of film;
• and
• operating said camera to make a continuous exposure of said mask object on the same said frame during said continuous adjustment while continuously varying at least one of the illumination of said mask obect and the effective exposure time to build up a margin portion having a light transmissability varying continuously from almost clear adjacent said clear portion to almost opaque adjacent said mask portion.

A method of making a master for a soft edge mask having a mask portion, a clear portion of light transmitting transparent photographic film and an intermediate margin portion and which method comprises:

• positioning a mask object in front of a photographic camera housing a photographic film;
• illuminating said mask object;
• operating said camera to make a first exposure in turn to provide a clearly focussed photograph of said mask object on a single frame of said photographic film;
• adjusting at least one of said mask object and said camera whereby to alter the size of the image of said mask object on said single frame of film;
• operating said camera to make a second exposure to provide a clearly focussed photograph of said mask object on the same said frame and;
• repeating said steps a predetermined number of times while varying at least one of the illumination of said mask object and the exposure time during said steps to build up a said margin portion comprising a plurality of strips having light transmissabilities varying progressively from almost clear adjacent said clear portion to almost opaque adjacent said mask portion.

A method of making a master for a soft edge mask having a mask portion, and a clear portion of light transmitting transparent photographic film and which method comprises:

• positioning a mask object in front of a photographic camera housing a photographic film;
• illuminating said mask object to provide a clearly focussed image of said mask object on a single frame of said photographic film;
• continuously adjusting at least one of said mask object and said camera whereby to alter the size of said image of said mask object on said single frame of film;
• and
• operating said camera to make a continuous exposure of said mask object on the same said frame during said continuous adjustment while continuously varying at least one of the illumination of said mask object and the effective exposure time to build up a margin portion having a light transmissability varying continuously from almost clear adjacent said clear portion to almost opaque adjacent said mask portion.