They go to airshows but are never interested in what is flying, instead they stand around in groups writing down a serial number of a plane they saw somewhere else. Writing it in their book that they have now seen it at an airshow but this time it has a scratch on it... or a different marking.
They carry one camera with a big lens on one shoulder, another camera with a small lens on the other shoulder. Their cap has badges all over it. Their bag has badges all over it.
They wear chequered shirts with dodgy trousers with white or black trainers (un branded) or sandles.