We went last Saturday and it was great fun - highly recommended, especially if the weather is good. Quite a few people brought chairs, cushions, big blankets and we even spotted a few duvets as well! Clearly some people are professional outdoor cinema goers... Most people brought picnics and there were quite a few champagne corks popping about which was amusing. The film started about 30 minutes late as they were waiting for sunset, and there was also a 15 minute intermission so it didn't finish up until 11:30 or so. We had to exit via the main gate which was a bit of a pain as there aren't really any buses back to East Dulwich from that side. It also gets cool quite quickly once it's dark so definitely bring something warm to put on.