Last time we had a black out, I tried to take photographs of smoke. We had two candles ready, one would be the source of light and the other the source of smoke. My sister had this theory that we had to let a candle burn long first before we blow it, so the smoke would be thick. I assigned her this task of just burning, blowing and holding the candles.
This photo here is a cropped and enhanced version. The original photo includes the other candle, the burning one, just beside the blown candle. I had other good smoke shots, however, the burning candle overlapped them. My sister couldn’t understand first that she has to position the burning candle so as not to overlap with the smoke. Anyway, it was a learning experience for both my sister and me, and candle smoke is beautiful. I don’t know if an incense candle makes better results. I have yet to try.