The rule of thrids, not to get yourself or your camera tangled up in stuff, is very useful. It’s no good chasing the perfect photo if you keep tripping up and breaking stuff. I learnt this the hard way: by the time I’d sorted myself out, the cliff had run out of lemmings. If only, I thought to myself afterwards, if only I’d remembered the rule of thrids, I’d have got the perfect downpour photo.