>>509013692>>509014698For what it's worth, if you want to get really autistic (or if a court decides to somehow question the accuracy of a GPS speed display), you can..
1) get the data google collects from your phone whether you are running maps or not. It will have coordinate pings every second. Do the math, get the speed
2) if your camera has audio and you aren't blasting the radio, you can take any of the noises like engine noise (RPM), road noise from tires. Correlate that frequency with a test where you purposely go out and travel at those speeds, compare the frequency - think like droning noises as you drive - and show that that they are the same. Although, you aren't going to see a big enough difference for something minor. This would only work if they're claiming you're going a decent clip over the limit
3) go back to the location, measure distances between lane lines, telephone poles, mailboxes, whatever. Go back to video, see how much time passed when gating these objects. Even do a re-run where you record but include your speedometer read out on a separate camera.