A picture taken for a DiDA upskilling task. A small white-ish candle on a piece of black card that had just been blown out. I put my camera in continuous shooting mode and chose the one with the most interesting smoke.
I bought blank A1 card in both black and white for macro stuff a while back, but have only used to white to date. I quite like the effect the black has, actually... I should use it more often in the future.