A method of calibrating one or more light sensors, in a target environment where each of the one or more light sensors is arranged to control a respective one or more light sources for providing or contributing to an illumination in the target environment, based on sensing a light level; the method comprising, for each of the one or more light sensors: a) measuring one or more light levels, by using the light sensor, corresponding to each of one or more illumination levels; wherein the one or more light levels is measured under one or more substantially non-zero levels of said illumination levels; characterized by further comprising b) identifying groups of one or more light sources, whereby the different groups are similar to one another in terms of their rendered illumination and are located in different environments and wherein templates comprising one or more template light level values (Et) are defined, wherein said template light level values are measurements from a light meter at the one or more illumination levels in one of reference environments of one of the groups, based on the assumption that said reference environment is approximately equivalent to said target environment, having an approximately equivalent illumination distribution, and that the light meter is placed at an approximately equivalent location in the reference environment to a target location in the target environment; c) receiving the one or more template light level values (Et) corresponding to each of the one or more illumination levels, wherein the template light level is representing a light level at a target location in the target environment, said target location substantially removed in space from a location of the light sensor and d) determining a relationship between the measured light level (Ls) and a light level experienced at the target location, by evaluating the one or more measured light levels relative to the one or more template light level values. a) measuring one or more light levels, by using the light sensor, corresponding to each of one or more illumination levels; wherein the one or more light levels is measured under one or more substantially non-zero levels of said illumination levels; characterized by further comprising b) identifying groups of one or more light sources, whereby the different groups are similar to one another in terms of their rendered illumination and are located in different environments and wherein templates comprising one or more template light level values (Et) are defined, wherein said template light level values are measurements from a light meter at the one or more illumination levels in one of reference environments of one of the groups, based on the assumption that said reference environment is approximately equivalent to said target environment, having an approximately equivalent illumination distribution, and that the light meter is placed at an approximately equivalent location in the reference environment to a target location in the target environment; c) receiving the one or more template light level values (Et) corresponding to each of the one or more illumination levels, wherein the template light level is representing a light level at a target location in the target environment, said target location substantially removed in space from a location of the light sensor and d) determining a relationship between the measured light level (Ls) and a light level experienced at the target location, by evaluating the one or more measured light levels relative to the one or more template light level values.