Answer
It is evidence that condensation conditions exist, so the aircraft and payload should be allowed to acclimatise and checked before flight.
Explanation
Visible lens fog can be a warning that less visible surfaces are also condensing moisture.
Drone exam · Meteorology
It is evidence that condensation conditions exist, so the aircraft and payload should be allowed to acclimatise and checked before flight.
Visible lens fog can be a warning that less visible surfaces are also condensing moisture.