Officials claim it would be impractical to publish a list of which cameras and lenses are allowed in Olympic venues
First, photographers and spectators for this month’s upcoming Olympic Games in London were outraged when they noticed their tickets said they couldn’t post any images online. But then the Olympic organizers admitted that it was pretty impractical. Next, just last month the London Olympic Committee officially announced that large cameras and lenses, specifically those over 30cm in length, as well as tripod and monopods will not be permitted in the 2012 Olympic Games (noting though that some venues—such as outdoor ones-- would allow it).
But it seems that even those clarifications, are still incomplete. For exemple, Wembley stadium, which will host soccer events, will prohibit any kind of "professional-style cameras (any camera with interchangeable lenses) or recording/transmitting devices." In other words, these rules mean that all DSLRs, as well as mirror less, compact interchangeable lens cameras manufactured by Panasonic, Olympus, Sony, Samsung, Pentax and Olympus are also banned.
A spokesperson declined to clarify the rules, saying: “It is generally felt that it would be impractical to publish a definitive list of cameras and lenses which would or would not meet the requirements, especially in view of the time constraints of a security test conducted on thousands of people entering a sports venue at a concentrated time,"
So if you have tickets to the London Olympics and wonder what camera and lenses to pack—don’t ask the organizers—pack your gear and take a chance.