Ananova:

More than 300 music fans who turned up at a university after seeing a poster advertising "An evening with rock photographer Tim Cullen" didn't get what they expected.

Instead of snaps of the world's greatest rockers like the Rolling Stones, the audience got a lecture on rocks given by geologist Tim Cullen.

The event was held at Nottingham Trent University, where people had expected to be shown pictures of Mick Jagger and other stars, reports the Sunday Express.

One audience member said: "I went to see the Stones, but not those sort of stones. Some of my friends walked out disappointed, but I decided to stay because I felt so sorry for the chap doing the presentation. "

Mr Cullen himself said: "It was rather embarrassing when they started shuffling off, but some were too polite to leave."