Why do other car headlights flicker in my side camera?

jdogcarroll

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To my tech geeks.. I was getting into an exit lane when I turned on my right hand blinker the camera popped up on the screen (as it should). However, the car that was behind me in that lane had flickering headlights (only visible in the screen) I freaked out and thought it was a cop... Anyone know why this would have happened? I am assuming something to do with a framerate? or refresh rate? I have no clue. Someone please enlighten me.
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NeoDragons

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it is most likely the refresh rate of the lane watch camera, especially if the car behind you had led headlights
 

Draken187

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it is most likely the refresh rate of the lane watch camera, especially if the car behind you had led headlights
Wouldnt that be backwards? Wouldnt it be the led headlights refresh rate being represented on the civics screen?

Op, to simplify record your led tv with your phones camcorder... Then replay the video you just recorded on your phone... It should do the same thing you experienced in the car.. Basically its picking up the refresh rate of the light wich our vision cant see
 

josby

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Yeah, the side camera outputs NTSC video, which has a framerate of 29.97 frames per second. LED lights can't be dimmed by varying the voltage like a incandescent light can. So if the light output of an LED bulb is higher than desired, it has to be pulsed on and off really fast to make it look dimmer.

If it pulsed on and off exactly 29.97 times per second (or some multiple of that like 59.94), then I think it would look solid through the side camera. But if the rate doesn't match the camera's like that, the camera records up some frames where the LED is on and some where it's off, so you see flicker.
 
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