Yes, but not all of them have road markings. If I got 'done' by one without them I'd take it to court and ask how they verified the speed. It seems that the Scamera Partnerships have got lazy and don't always bother to put the calibrations on the road.

99.9% of the population just cough up when caught, even though many people are incorrectly charged with speeding. They work using radar, and it's notoriously inaccurate, as the signal can bounce of stuff like passing lorries, bus stops, armco etc... It's all bullshit, but all the while the public just accept it they'll keep putting cameras up.