Method and apparatus for exposure control of a selective laser sintering or laser melting apparatus

The invention relates to a method for exposure of a selective laser sintering or laser melting apparatus for producing three-dimensional objects, comprising the steps of: Providing a selective laser sintering or laser melting apparatus in which three-dimensional objects at the corresponding locations can be produced by successive solidification of layers of a solidifiable by radiation powdery building material of each cross section of the object, wherein the apparatus provided includes an irradiation device for irradiating layers of the building material, a plurality drivable of separately, at the same time the building material irradiated scanners having the separate detection of the irradiation times of each individual scanner and / or detected by each individual scanner irradiation areas in a first step and storing the detected irradiation times and / or radiation surfaces; Comparison of irradiation times and / or radiation surfaces of the individual scanner with each other; Redefining the to be irradiated by each individual scanner surface areas of a powder layer such that the irradiation times for each individual scanners are approximated to each other as possible and / or the irradiation areas of each individual scanner are in area aligned as far as possible to each other.