Took this today along with some other lighting experiments.. manually fired flash. Only some minor pp - erase a few stray light specks, subject wasn't touched at all.
Flash wasn't mounted on camera so that I could fire it from the side.. trying to put things off balance.
Wondering whether I should have bumped up the flash a bit more? The overall effect is rather dark, but not too sure whether that's good.. looking at others' photos (with sparklers etc) a stronger flash seems to be the norm to show the subject more clearly.