Blended internal latent image emulsions, elements including such emulsions and processes for their preparation and use

A photographic element including

• a support and,
• as a coating on said support, a photographic silver halide emulsion layer comprised of silver halide grains internally sensitized with a combination of the same middle chalcogen and noble metal sensitizers capable of forming on exposure an internal latent image,
• said emulsion layer being the product of blending at least two silver halide emulsions each comprised of silver halide grains internally sensitized with the same middle chalcogen and noble metal sensitizers, a first of said blended emulsions being comprised of lower contrast producing silver halide grains exhibiting a comparatively higher proportion of middle chalcogen to noble metal internal sensitization and a second of said blended emulsions being comprised of higher contrast producing silver halide grains exhibiting a comparatively lower proportion of middle chalcogen to noble metal internal sensitization, said higher and lower contrast silver halide grains being otherwise substantially identically internally sensitized.

A process of modifying a photographic silver halide emulsion capable of forming on exposure an internal latent image to exhibit a desired characteristic curve comprising

• providing a first photographic silver halide emulsion comprised of silver halide grains internally sensitized with a combination of middle chalcogen and noble metal sensitizers capable of forming on exposure an internal latent image and
• blending therewith a second, higher contrast photographic silver halide emulsion comprised of silver halide grains internally sensitized with a relatively lower proportion of middle chalcogen to noble metal sensitization, wherein the same middle chalcogen and noble metal sensitizers are present in the first and second emulsions and said silver halide grains of said first and second emulsions are otherwise substantially identically internally sensitized.