Flood light: floods a close area with light
Spot light, narrow beam of light that goes for.. miles.
Car headlights are sort of a mix between the 2 .. a spot that spills quite a bit light outside the edges.
So it sort of like sound proofing, weather to insulate or or to stop reverberation depends very much on source, sound and type of panel.
Back in the day (way pre leds) I put flood on the top rail behind the cab on my datsun ute (thats goes back a bit and was brand new)...reflected light back ff the hood, and in rain, hopeless... but excellent for lighted work area in front.
Then added with a couple spots (interdependent circuits) and if directed beams to miss the end of the hood (bonnet) excellent... as work lights, lot dark shadows, limited area from each spot.
Floods reflect real bad
That little spot on the front cnr of of my cabin, does work reasonably , other wise would have removed it yrs ago.
It is angled to just miss the bow, but still slight spillage/ reflection...But still see the water out in front enough to pick up anything un lit traveling at speed on flatish water, and slower speed with bit of swell/ chop.
Going towards harbour , moorings etc ...the beam is too narrow to pick up stuff when direct changes.
And thats when the hand spots by crew come in.
Now effective hand spots by crew is very dependent on instructions of what you need at the helm.
Basically they pick out and object/ obstacle up front on their side of the boat... and hold that object in the beam until we have nearly drawn level, then go to the next , and next... Do not shine it directly on other boats, shore or people.. that really p155es my off so I make a point of not doing it
I thought about going to those remote control spots..then scraped the idea, rightly or wrongly, not just because of the cost..reason was ideally need 2 spots for both sides... like car headlights go (sort of ) left and inside the center line of the road. So at the helm, watching controls , then add to that , remotely moving spots from one object to the next, steer...
That spot on the front cnr of the cabin, thu not as good as would like has picked up a log out off Anita (bottom end) couple times a small un lit dingy fishing in Waiheke channel, a kayak off dudders, couple long line bouys off the front of pakatoa...all at bottom end of cruise speed in a slightly choppy water to flat.