A method of setting up a dialysis treatment in a dialysis machine may include the steps of determining conditions of a dialysis treatment adapted to a specific patient, determining a first function ) of a first quantity characterizing the dialysis treatment as a function of time, and determining a second function ) of a second quantity characterizing the dialysis treatment. The micro-lenses of the micro-lens array are configured to focus light incident on the sensors, into the sensors. In order to determine the quantum absorption events particularly precisely, in at least one embodiment it is provided that the detector pixels have at least two mutually different pixel apertures.