I have a speed camera fine, but picture is of rear of car?

How can we id the driver if the picture from a cash camera van is taken of the back of the car, any loopholes here? Also it says I'm doing 49 in a 30 which i believe is nonsence, as i drive the road daily and the road ddoesn'tlend itself to that speed i.e its up a hill and parked cars on the left, i have been seen off, serious answers please.