Photographic element having improved magenta dye light stability and process for its use

The invention provides a photographic element comprising a silver halide emulsion layer having associated therewith a dye-forming coupler represented by formula I: wherein X is hydrogen or a coupling-off group; and R' is a tertiary alkyl group and R'' represents the group in which R1, R2, and R3 are independently selected alkyl groups, provided that any two of R1, R2, and R3 may join to form a ring; R4 is hydrogen or a substituent, provided that R3 and R4 may join to form a ring when R4 is a substituent; and W is a substituent selected from the group consisting of -C(O)R5, -SO2R5, and -P(O)(OR6)2 in which R5 is selected from the group consisting of alkyl, aryl, alkoxy, aryloxy, alkylamino, and arylamino groups and R6 is selected from the group consisting of alkyl and aryl groups. The element exhibits improved magenta dye light stability.