Just another one of the Queen’s Jokes
It is quite evident that Her Majesty was taken aback to witness such a large number of cameras running at the same same moment as each other. At this point, she ought to be aware that every action that she takes while she is in a public area is being intently observed by a huge number of other people who are paying attention to what she is doing because they are paying attention to what she is doing.
Because they are paying attention to what she is doing, these other people are paying attention to what she is doing as well. These people are paying attention to what she is doing because they are paying attention to what she is doing, and therefore these other people are paying attention to what she is doing.