The question: Are historic license plates – the yellow, black and blue plates from the 1950s, ‘60s, and ‘70s – readable by automatic plate readers?

The answer:  No, at least in Santa Rosa, because the color contrast and fonts of the letters and numbers, which confuse the machines. Janet Reisner, supervising parking enforcement officer, says the vendor that created the plate reader system reports that it might be possible to modify the system to read the older plates, but they didn’t see it as a necessary feature because of the small number of old plates out there.

And even so, having a classic plate isn’t a get-off-free card for parking scofflaws who overstay timelimits, Reisner said, because the city’s parking enforcement system has multiple methods of identifying cars, including a laser-based device that recognizes vehicles by their size, shape, and color.

In any case, the human officer operating the system can easily do manual checks on the license plates if the machines don’t read them correctly. The officers are accustomed to having to double check all the machines they use, since even the sophisticated laser system sometimes has trouble distinguishing between cars of similar shapes and colors, so checking manually on classic car plates that don’t read properly isn’t a major distraction.

The state is now considering issuing reproductions of those classic plates and the Department of Motor Vehicles says they will meet modern standards, including using easy-to-read reflective characters.

Reisner said the city has not heard whether the reproduction plates will be easily machine readable, but if not, the creators of the system “can tweak that – they’re very smart.”


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