A system with a detector array, a processor unit and a signal interface. The detector array includes a plurality of bolometric measuring cells and a base body. Each measuring cell is configured to detect infrared radiation and to transmit a measurement signal, which is representative of the readings of the measuring cells, to the processor unit. The processor unit is configured to determine a body heat stored by the base body, to determine a predictive value compensated according to the time delay of the respective measuring cell for each current reading, to determine a temperature value corrected according to the measurement error for each current predictive value, and to determine a thermal image based on the current temperature values, allowing an image signal representing the thermal image to be sent from the signal interface. A corresponding method is also provided.