"I'd like a large snifter of brandi, please."
I always like to see this old 1980's style shot of girl + bikini + water being poured + flash...it's a shot that never has completely gone away...it really depends on the exact, specific flash duration for impact, and how the water is rendered...if the flash duration is too brief, the water looks, well "weird"...ambient light can also play a role in how the water appears...matching the background lighting to the flash exposure usually makes the water look a bit "odd"...the water splashing off of her and going out to the sides has a slightly unnatural look where it shows up against the blue water. Not that it is "bad" or "good"--I'm just talking about the way moving water is rendered by flash or flash + ambient continuous light---this is a classic Playboy-style technique, covered somewhere in the past by I think it was longtime Playboy top shooter Arney Freytag in some video presentation I saw 'somewhere', years back. He showed some outtakes...they looked "not so good" because the flash was too brief, and making the water droplets look too frozen...and then some shots that had too much ambient light, and too much flash, so the water had a weird, unnatural "ghost image" type look of ambient light blurring + frozen flash that just visually appears "faked". The exact, right flash duration for the water being used, and for the ambient light level, and the images had a simply magical feel to them.
The ONLY way I know to control the flash duration 100 percent repeatably is to shoot in Manual mode, at fractional power levels; automatic or TTL flash can yo-yo the flash duration all over the place, depending on how close the flash is to the subject, and a whole host of variables. Or to use a studio flash with a known duration, at a specific power level.
Anyway...yeah...I always have enjoyed seeing this kind of shot. One thought is that the water stream itself will show up QUITE well if the water is backlighted by the ambient light, and the foreground/subject is shown somewhat darker...usually seen in a location where there is a doorway or wall in the foreground, with the model in what amounts to 3- to 4-stop backlight, with the backlight shining through the descending water, and then the flash freezing the droplets...