On 08/06/2018 14:56, Dave Plowman (News) wrote:
In article ,
Fredxx wrote:
It's not. Having the light source - in this case infra-red - beside the
lens means it reflects straight back into the lens.

If the IR illumination and camera were perpendicular to the number plate
I would agree, but that would be unlikely. The only other issue is with
snow/rain/fog where there is significant local reflection.

Car number plates reflect light from more than one direction.

By law the letters shouldn't, nor should any coating be added to make
the letters retro-reflective. So the contrast should be huge.