Method and device for controlling an illuminance

For controlling an illuminance of an actual value of a sensor (3) is interrogated, which depends on the to be controlled illuminance and to be controlled to a desired value. An electronic computing device (11) determined in a control step includes a detecting step for a luminaire (2) in dependence on the actual value and a parameter value of a control parameter. The electronic computing device (11) determines a new parameter value of the control parameter for a subsequent control interval depending on a first actual value is received before the corresponding control step, and a second actual value, which is determined according to the corresponding control step.