Originally Posted by Ribald
Regarding spot lights. One quick thought occurs to me - probably not a good idea to go shining a powerfull light directly at the offending boat heading towards you. You don't really want to be in the path of a boat being helmed by someone who's just had the back of his eyeballs toasted by 1 million candle power 'cause he won't be seeing anything at all for at least a minute....... Far better to either illuminate your boat or sweep the light from side to side but low down.
Spot on Peter.
If anyone shines a light in my eyes I will be very unhappy.
Just think what it is like when some twit forgets to dip his headlights.
Human eyes work well in low light conditions (not pitch dark) and exposing them to any
white light kills your night vision considerably for several minutes.