An indication system for a surgical lighting apparatus is provided, comprising a computer device connectable to a plurality of light modules, wherein the computer device is configured to determine an illumination setting for each of the plurality of light modules; compare the illumination settings of at least two of the plurality of light modules to at least one output illumination threshold; and output an indication if the at least one output illumination threshold is exceeded. A surgical lighting apparatus, a method of indication, and a detection system for a surgical lighting apparatus are also provided.