A method of forming an image is provided. The method comprises the steps of (a) imagewise exposing a photographic material which comprises a support having provided thereon at least one light-sensitive silver halide emulsion layer and which contains a hydrazine compound represented by the following general formula (I) in the emulsion layer or a hydrophilic colloid layer adjacent thereto, the photographic material being designed so that a difference in sensitivity (sensitivity being defined as log E corresponding to the density of fog+2.0) between (1) the photographic material is development-processed with a developing solution having a sulfite ion concentration of 0.15 mole/l or more, a potassium ion concentration of 0.2 mole/l or more and a pH value ranging from 10.5 to 12.3 and (2) the photographic material is development-processed with the same developing solution as described above, except that the pH value was lowered by 1.0, (.DELTA.log E), is 0.7 or less, and moreover, the gamma value obtained in (1) is 10 or more and the gamma value obtained in (2) is 5 or more: ##STR1## wherein A represents an aliphatic group, or an aromatic group; B represents a formyl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkylsulfinyl group, an arylsulfinyl group, a carbamoyl group, an alkoxycarbonyl group, an aryloxcarbonyl group, a sulfinamoyl group, an alkoxysulfonyl group, a thioacyl group, a thiocarbamoyl group, a sulfamoyl group, or a heterocyclic group; both R.sub.0 and R.sub.1 represent a hydrogen atom, or one of them represents a hydrogen atom and the other represents an alkysulfonyl group, an arylsulfonyl group, or an acyl group; and B, R.sub.1 and the nitrogen atom attached thereto may form a partial structure of hydrazone, and (b) developing the exposed material with a developer. The method realizes superhigh contrast and high resolution images.