We do the same when hunting from a boat, one on the boat keeping an eye on the divers in the water and use signals for certain circumstances, gun handle up for a shark, gun point up for a fish pick up, wave for a pickup of diver and a 'roll' with the arms by the boater to indicate that its time to be picked up, we do this so you dont have float lines in the water that mite get into the props. I like your idea of a signal flasher for night dives, but what about having it on a float with a shortish line connected to the divers weight belt, I know these are cumbersome at night but it mite be more visible...
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Dive safe and shoot straight
- Hénré -
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"Thinking is the hardest work there is, which is probably why so few engage in it"
- Henry Ford -
