There is an organisation in the UK campaigning against cameras - this is their site. They have been through all the thinking you are just getting involved in and can therefore save you a lot of effort.
http://www.safespeed.org.uk/index1.html
The association of british drivers site could also be interesting.
http://www.abd.org.uk/
This is the site of a company manufacturing cameras and shows some of the advances in design and automation of the processes.
http://www.redspeed-int.com/en/products_redspeed.htm
Modern cameras are digital, connected by computer network to a mainframe, need no film, identify the vehicle from the number plate, create the fine ticket on a mainframe computer and it is sent to you without any police involvement.
A recent development has been SPECS cameras which measure your average speed over a distance (like a mile or two) and send you an automatic fine.
One camera alone in England has collected over a million pounds in fines in a year.