actually, the colour of PS853 is wrong. its not a true PR blue. PM631 is nearer although I think they used Landrover Blue for that 1 because PR blue is hard to come by. the last aircraft to carry PR Blue were the PR9 Canberras
THe colour of PS853 is indeed incorrect. I spoke to the guy who looked after her at East Midlands a few years ago and he said that they had tried hard to find out what colour had been used for her when she was restored without any joy.
The incorrectness of the colour is more obvious when you see the original blue which is visible in certain areas when various panels etc are removed.
Despite the wrong colour she still looks rather nice though dont she?