The invention relates to a process for dyeing and/or lightening keratin fibers using i) particular dye(s) and/or pigment(s), ii) photoactive compound(s) and iii) light source(s); a cosmetic composition comprising the ingredients i) and ii); the use of ii) for improving the fastness and/or dyeing and/or lightening of keratin materials in the presence of the ingredients i) and iii) of light source(s), and a multi-compartment device comprising i), ii) and iii). The implementation process and the use i) of particular dye(s) and/or pigment(s) combined with ii) the photoactive compounds and iii) with a light source make it possible especially to obtain lasting coloration on keratin fibers without the use of a reducing agent, and without odor.