Abstract: A method is disclosed of preparing of a photographic silver halide emulsion comprising precipitating in one or more precipitation steps in a reaction vessel, followed by desalting by means of flocculation and washing or by means of ultrafiltration, said emulsion comprising gelatin as a binder and {100} tabular silver halide grains containing at least 50 mole % of chloride, wherein at least 40% by number of all grains is provided by said tabular grains, and wherein said tabular grains exhibit an average aspect ratio of at least 2, an average thickness of at most 0.5 .mu.m, and an average equivalent circular crystal diameter of 0.3 .mu.m or more, characterized in that during said precipitation step(s) said gelatin binder present in said reaction vessel is substantially free of calcium ions and is oxidized to a degree in order to have a methionine content of at most 4000 ppm.

Abstract: A method is disclosed for the preparation of tabular silver halide emulsion grains rich in chloride and showing (100) parallel major and an average aspect ratio of at least 2.0 in silica sol as protective colloid binder. Important parameters are the addition modalities of the silica sol and the ratio of its amount to the amount of a costabilizing onium compound.

Abstract: A method of reproducing an electronically stored medical image on a hardcopy material is disclosed, said material comprising a support and on only one side thereof a silver halide emulsion layer and a hydrophilic colloid layer, wherein said emulsion layer comprises red sensitized homogeneous cubic silver chloride, silver chloroiodide, silver chlorobromide or silver chlorobromoiodide crystals having not less than 70 mole % of chloride ions and preferably not less than 90 mole %; not more than 1 mole % of iodide ions and an average crystal size of from 0.12 to 0.30 .mu.m and more preferred from 0.15 to 0.25 .mu.m; wherein said crystals are coated in an amount, expressed as an equivalent amount of silver nitrate of from 2 to 6 g per sq.m.

Abstract: A photographic light-sensitive silver halide material is provided for making negative lithographic images or direct-positive images, said material comprising a support, at least one internal latent image-type silver halide emulsion layer (in the case of direct-positive materials) or surface latent image-type silver halide emulsion layer (in the case of lithographic materials) and development-nucleating amounts of a compound or a precursor thereof, said compound having at least one quaternary heterocyclic ring system comprising at least three rings including a tetrahydropyridinium ring wherein carbon-nitrogen and carbon-carbon double bonds are also part of an aromatic ring being one of said three rings and wherein said double bonds and nitrogen atom in said tetrahydropyridinium ring are incorporated into annelated conjugated ring systems. Developing said photographic material after exposure in an alkaline surface developer rapidly converts said precursor into a ring system as defined hereinbefore.

Abstract: A method has been disclosed of processing an exposed silver halide photographic material comprising at least one coated hydrophilic silver halide emulsion layer comprising tabular grains rich in chloride, bounded by [100] or [111] major faces, characterized by the steps of developing, followed by fixing, rinsing and drying the said material, wherein developing proceeds in a developer, comprising hydroquinone in an amount from 0 to 30 g per liter, an auxiliary developer, as silver halide complexing agents alkali metal sulphite salts in an amount from 1 to 50 g per liter, at least 1 g of a compound corresponding to the formula (I), a precursor thereof, a derivative thereof and/or a metal salt thereof ##STR1## wherein the substituents are defined in the main embodiment of the specification.

Abstract: A photographic developing solution and a method of developing silver halide materials in the said developing solution is disclosed, the said developing solution comprising hydroquinone in an amount from 0 to 30 g per litre, an auxiliary developer, and silver halide complexing agents in an amount from 0 to 50 g per litre, characterized in that said developer further comprisesin amounts from 0.1 to 5 g per litre a compound corresponding to the formula (I), accompanied by charge compensating anions,Z'N.sup.+ --R--N.sup.+ Z" (I)wherein at least divalent group R contains at least one oxyethylene group and wherein Z' and Z", being the same or different, are composed of enough atoms to form a heterocyclic aromatic 5- or 6-ring;andat least 1 g of a compound corresponding to the formula (II), a precursor thereof, a derivative thereof and/or a metal salt thereof ##STR1## wherein each of A, B and D independently represents an oxygen atom or NR.sup.1 ;X represents an oxygen atom, a sulphur atom, NR.sup.2 ; CR.sup.3 R.

Abstract: A new type of hydrazide compounds is disclosed corresponding to general formula (A): ##STR1## the symbols of which are explained in the description. Examples of synthesis are given. Incorporation of these diacyl hydrazides into the silver halide emulsion layer(s) of a photographic material causes a significant increase in sensitivity.