Silver halide photographic emulsion

A silver halide photographic emulsion spectrally sensitized with a combination of at least one sensitizing dye represented by the following general formula (I):

• ##STR14## wherein Z.sup.1 and Z.sup.2 each represents the atoms necessary to form a benzothiazole nucleus or a benzoselenazole nucleus, R.sup.1 and R.sup.2 each represents an alkyl group or a substituted alkyl group wherein at least one of R.sup.1 or R.sup.2 represents a sulfo group-containing substituted alkyl group, a carboxyalkyl group or a hydroxyalkyl group, R.sup.3 represents an alkyl group, X.sup.1 represents an acid anion, and m represents 1 or 2, wherein m equals 1 when the dye forms an intramolecular salt (betaine-like structure);
• at least one sensitizing dye represented by the following general formula (II):
• ##STR15## wherein Z.sup.3 represents a sulfur atom or a selenium atom, Z.sup.4 represents the atoms necessary to form a benzothiazole nucleus, a benzoselenazole nucleus, a naphthol[1,2-d]thiazole nucleus or a naphtho[1,2-d]selenazole nucleus, R.sup.4 and R.sup.5 each represents an alkyl group or a substituted alkyl group, wherein at least one of R.sup.4 or R.sup.5 is a sulfo group-containing substituted alkyl group, a carboxyalkyl group or a hydroxyalkyl group, R.sup.6 represents an alkyl group, an aryl group, a furyl group or a thienyl group, X.sup.2 represents an acid anion, and n represents 1 or 2, wherein n equals 1 when the dye forms an intramolecular salt (betaine-like structure);
• and at least one benzimidazolothiacarbocyanine dye represented by the following general formula (III):
• ##STR16## wherein R.sup.7 and R.sup.8 each represents an alkyl group or a substituted alkyl group, R.sup.9 represents an alkyl group containing up to 4 carbon atoms, W represents a hydrogen atom, an alkyl group, an alkoxy group, a hydroxy group, a halogen atom or a phenyl group, X.sub.3 represents an acid anion and p represents 1 or 2, wherein p equals 1 when the dye forms an intramolecular salt (betaine-like structure).