discrepancy
Contributor
fotoleaf:...I am planning to do underwater portraits in an indoor swimming pool and curious if you think one strobe would be enough. Would it create harsh shadows? Would I need an additional strobe for fill light? opinions?
I think I see where you're coming from with your question about fill lighting. For portrait shots on land you would traditionally look for a highlight/shadow ratio of no more than 3:1 EV for flattering shots of women, and maybe up to 5:1 for craggy men with character. And 'Rembrandt' lighting is a professional standard.
Can you re-create this ideal underwater? Short answer is it's hard at anything below 10m/30ft with one strobe. At depth you'll either get backscatter from particulate matter if your strobe is close to face-on, or harsh oblique shadows if you angle it off. That's physics.
But you should get some very pleasing results in a pool because sunlight effectively gives you the high, angled highlight lighting for free, and you can adjust your single stobe to provide the fill in.
Diffusing covers will add a nice soft lighting to your shallow-water shots, just as they do on land, but also remember that a diffuser will cut your flash number down by about 1/3 at depth, and that could mean getting a shot with half-decent colour, or not.