The invention relates to a method for directly producing fine-particle 1,4-diketopyrrolo[3,4-c]pyrrols of formula (I), wherein R1a, R1b, R2a and R2b independently represent hydrogen, halogen, C1-C4 alkyl, C1-C4 alkoxy, cyano or phenyl, the compounds being characterized by a maximum frequency distribution between 20 and 120nm. According to the method, nitriles are reacted with succinic acid esters or lactames or enamines in an alkali medium to form a pigment alkali salt, and then protolysis of the pigment alkali salt is carried out. The method is characterized in that an effective quantity of a pigment dispersant of formula (II) is added during the protolysis of the pigment alkali salt. In formula (II), Q is a radical of an organic pigment from the group of perinone, quinacridone, quinacridonquinone, anthanthrone, indanthrone, dioxazine, diketopyrrolopyrrol, indigo, thioindigo, thiazineindigo, isoindoline, isoindolinone, pyranthrone, isoviolanthrone, flavanthrone or anthrapyrimidine pigments.