This was back in the days of film when one of my clients was South Carolina State Parks.  It was after sunset on an incredibly calm summer evening.  If I recall correctly the exposure was around 20 seconds or so and the boat was so motionless that it is still sharp.  It was the last exposure of the night before I called it a day and went back to my tent for the night.  To think I actually had to wait several days before picking up the film from the lab to see the results……… boy have things changed in this business.