In regards to the specifics of one operation in which accurate distance estimation can be helpful. Other operations in other trades will be widely different:
In terms of landing a boat at a dock: Imagine a U-shaped basin of docks. Imagine each side of the “U” is two boats longs. Maybe 600 feet on a side. Imagine near one of the corners of the “U”, where a side meets the “bottom”, there is a berth open. Maybe one boat-length long plus 10 feet. The skipper has to land his boat in that berth, with a vessel moored ahead and astern, with five feet to spare from each boat. Skipper probably has a single thruster. But maybe not. Maybe twin screw. Maybe single screw. Never a tug. If it’s one of our house forward boats, the skipper can’t see the stern from the wheelhouse because of the raised poop. Imagine the wind at 40 knots, setting the boat down into the basin, and it’s driving rain. Imagine plenty of boats milling about the basin, and it’s the middle of the night. The skipper has himself, one mate, maybe a couple of trusted ABs to shoehorn the 260’ boat in the 270’ slot. A few other hands to handle lines, but no one else to rely on to conn the boat in.
That’s a fair description of the environment our boats land and depart in, and the context in which I was inquiring about rangefinders Not the worst conditions, but fairly challenging. Throw in Dutch Harbor williwaws, where storm force winds can completely reverse directions within a matter of minutes and close-quarters boat handling can become difficult. A near sighted AB, simultaneously talking on the handheld and fast-coiling his heaving line before it gets sucked in the wheels, after missing the dock, in pouring rain, can be excused not getting distances exact, when the relative positions of docks and boats, both fixed and moving, are changing fast. But after an internet search I can’t find any technology that would help in this case. There is a saying we have “Dutch Harbor is where technology goes to die”. All the electronic devices which seem so rugged elsewhere usually expire after a day or two of Aleutian winter.