If someone or something is not a child and is in a public place, or a place were the public is permitted, any picture is copyright of photographer, and you don't need permission to take a picture. Don't put it there if you don't want it photographed. Somewhere you are 'invited' to visit, ie a museum can set their on rules. MOD property is the fifedom of the Secratary of State, who may declare any area 'Restricted' and forbid photgraphy. This was a pain in the ass for me as a photo of my old 101 ambulance has become a stock picture. If I could have claimed royalties it would have paid for her! :mad:
Mind you, at Sandhurst a few years back they had some real drool value kit. I did ask if I could take pictures and got told 'Fill your boots', well three cards anyway.