Quality-Checking the Red Light Camera Databases
How accurate are the red light and speed camera detectors?
By Connor Chase
Last updated: 2017
The colorful acronym GIGO is credited to George Fuechsel, a fifties-era computer programmer. Way back when ENIAC was cutting-edge technology, Fuechsel presciently cautioned, "Garbage in, garbage out", i.e., the quality of the information produced by a computer is dictated by the quality of the information entered into it.
We wondered if Fuechsel's cautionary aphorism also applies to the heart of every GPS-enabled radar detector: its digital list of camera locations. So we set out to answer two big questions: Exactly what constitutes a superior location database? And, which one is the best?
One crucial task we quickly identified: keep it up to date. New cameras can literally appear overnight and adding a site weeks or months after it becomes active simply isn't good enough.
How We Tested Them
We first narrowed the project's scope to four states—Arizona, California, Colorado and New Mexico—and zeroed in on six large metropolitan areas. Next, we compiled our own database of camera locations. Then we placed a test fixture in our target car, installed the radar detectors and drove to the 128 camera locations we'd identified, veifying each camera. Learn more...
In total we verified 96 working cameras. Another 11 sites had no cameras, poles or wiring. All had either previously been photo-enforced and since abandoned or announced as future sites, but with no cameras yet installed. Two sites were under construction.
All of the remaining cameras were phantoms, many of the locations having been supplied by websites like photoenforced.com. Other sites also offer this information either for free or at a nominal cost.
We found the Aura database precise in its location-marking, allowing a Cobra GPS-enabled radar detector to reliably alert at the appropriate moment. It was also very reluctant to issue phantom alerts to cameras that are either nonexistent or which are merely traffic surveillance units.
We noted, however, that the Aura system trails the Escort Defender at deleting outdated locations, making it more prone to warning of cameras removed years previously.
The Cobra Aura database showed excellent accuracy against cameras that had been active for a few years. But newer installations seemed to be problematic.
For example, each of Tucson's speed cameras had arrived within the past 120 days: the Aura database missed all 10 of them. At the time of our visit, metro Denver's cameras had all been in service less than 18 months and the Aura missed 13 of the 13. When we crunched the numbers we found that it had alerted us to only 66 percent of the cameras in the test.
In contrast, the Escort Defender database alerted us to 95 percent of the cameras. Defender also mapped camera locations accurately, enabling our test units to warn of most of the cameras.