I have accurate knowledge concerning the redflex systems cameras. the system works by not only taking several stills of the infraction rear of the vehicle, driver's face shot, overall of the scene, but also 3 seconds prior to and following the infraction. this is why the plate covers that just obscure the numbers don't work, and the ones that over expose the shot don't because of the non-flash video. as far as an LCD cover that went completely black or opaque that may work, or the flash may be bright enough to get a reflection off the covered plate. A flip plate, I think would be the best answer. But don't get caught by a live officer, as they wouldn't take to kindly to covering/hiding the registration information from public view.
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