The FlightScope Mevo+ uses Advanced Fusion to record the Face Impact Location on your shots. FlightScope's Advanced Fusion Tracking feature requires sufficient lighting to collect accurate data. The minimum light measurement in your hitting area to achieve this is 300 lux. Because this is the minimum requirement, we recommend lighting the area so that you achieve a lux reading higher than 300 with a lux meter in an area with a 3 foot (approximately 0.9 meter) radius measured from the hitting location.