this post was submitted on 24 Aug 2025
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cross-posted from: https://sh.itjust.works/post/44712264

These up-eds usually complain that photo radar would be fine if the radar worked properly. This one doesn't even do that. It just complains that speed limits aren't fair and now drivers have to change their behavior. jfc

It is true that drivers can avoid such tickets by sticking to the posted speed limits, but it is also true that drivers are hardly ever expected to strictly observe those limits.

...

It’s like the generally accepted contract between drivers and police – just drive at a reasonable speed and you’ll be fine – has been broken.

https://www.theglobeandmail.com/opinion/article-photo-radar-is-becoming-increasingly-common-that-doesnt-make-it-any/

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[–] infinitesunrise@slrpnk.net 4 points 1 year ago* (last edited 1 year ago) (1 children)

I don't know what "photo radar" is and at this point I'm too afraid to ask.

[–] cvieira@lemmy.ml 4 points 1 year ago* (last edited 1 year ago)

TL;DR: it's speed cameras

Most radar guns work a bit like a flashlight. They just blast radio waves in the direction they're pointed, and some of those waves hit things and bounce off. The frequency of the reflection can be used to calculate the speed of the object (i.e. vehicle) relative to the observer, sort of like how you can tell if a train horn is headings towards you or away from you based on the pitch.

Photo radar is a fair bit more advanced, and can pick out individual vehicles. With traditional radar, and human operator has to visually identify a speeding vehicle, and the radar gun is just meant to be a confirmation of the officer's observations. Photo radar makes it possible to automate the process to reduce cost, even with multiple vehicles.