One time bedding in brakes down the lonsdale highway I went from 100 to 40 pretty hard, looked up and there was a cop car in the bushes dead ahead of me, went past and got a couple of flashes a few seconds apart and absolutely shat myself, to this day no fine (about a year) so probably was just a cop giving you a warning.
The newer ones that you see on the camrys with the long black bar take an IR photo and do not flash.
Sorry for the (slight) necro but thought it important to clear up that they can now take flashless photos.
And here's a scary one that exists but luckily not in Australia yet!