The present application provides cyanine dyes of the formula (I) in which R1, R2, R3, R4, R5 and R6 mutually independently denote a substituent, providing that at least one of the residues R1, R2, R3 denotes an indolyl substituent, X denotes O, S, Se, NR9, CH═CH or C(CH3)2, wherein R9 denotes a optionally substituted alkyl residue, R7, R8 mutually independently denote alkyl, sulfoalkyl, carboxyalkyl, —(CH2)1—SO2−Y—SO2—alkyl, —(CH2)1—SO2—Y—CO—alkyl, —(CH2)1—CO—Y—SO2—alkyl, —(CH2)1—CO—Y—O—alkyl or —(CH2)1—NH—SO3&thgr;, —(CH2)1—N(alkyl)—SO3&thgr; or —(CH2)1—N(aryl)—SO3&thgr;, providing that l=1 to 6 and Y means NH or N−, n means 1, 3, 5, 7, L denotes a substituted or unsubstituted methine group, which may be a constituent of one or more carbocyclic rings, and M denotes a counterion optionally necessary to equalise charges, as well as color photographic materials containing cyanine dyes of the formula (I) and the use of compounds of the formula (I) as spectral sensitizers.