Electronics > Beginners

Will the attached 100Hz flickering light output cause a problem for CCTV?

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ocset:
Hello,
Supposing there is a LED streetlight which flickers as in the attached. (that’s actually the light output, not a voltage). As you can see, the light output actually goes to zero every 10ms.

Will this cause a problem for CCTV  cameras at night ?
Will this cause a problem for Number plate recognition cameras at night?
Will this cause a problem for police dash-cams at night?
Supposing if the exposure time is 1ms, and it takes 1 picture per second, then surely in theory the images could all be black?

Karlo_Moharic:
Your best bet is to just grab a CCTV camera (type & model you are planning to use) and try it in real life conditions. This is because different cameras use different sensors so the only way you can be certain in anything is to just try it out.

Gyro:
You've already asked...

https://www.eevblog.com/forum/projects/100hz-flicker-in-lighting-is-a-problem/msg1775726/?topicseen#msg1775726


P.S. That .jpg you've attached is just full wave rectified AC waveform, not the light output waveform of an LED Streetlight.

janoc:
Treez, why are you still trying to find a justification that your crappy 100Hz flickering LED is somehow an acceptable design? All that after two pages of discussion in that other thread where it was clearly explained to you that cameras are likely the least of your problems there!

Put a bloody capacitor at the output of that rectifier and be done with it. This is beyond ridiculous. What will you do when your employer gets sued because someone got distracted by that high powered stroboscope of yours and crashed their car?

BTW normal CCTV camera will likely not capture the individual flicker (they run much slower than 100Hz) but the automatic gain control will likely be mightily confused by that flicker, with some frames being overexposed and some underexposed.

eliocor:
DEAR treez PLEASE DO NOT GIVE ME A 'THANK': I found offensive to your person your way of thanking everyone!!!
--- Quote ---Will this cause a problem for Number plate recognition cameras at night?
--- End quote ---

to my knowledge (at least in Italy*) every plate recognition camera (also Police ones) during night works:
- using pulsed infrared light (at various levels to be sure to not be fooled)
- using the retoreflector treatment on the plate to get an high image contrast
The same can be said for almost any CCTV camera: under a certain level of light they disable the IR cutoff filter and turn to IR vision.
So your question(s) [at least for those case(s)] are useless because visible light will not affect camera vision.
 
 
*) I think also in the rest of Europe, being car plates almost "unified": https://en.wikipedia.org/wiki/Vehicle_registration_plates_of_the_European_Union

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