Friends who love photography will find that whenever we pick up the camera to take a photo, if we happen to encounter an LED light, it will flicker on the camera. However, it is normal to see the LED light with the naked eye. So why does the LED light flicker on the camera?
Firstly, we need to understand that the frequency at which LED light sources flash is imperceptible to the human eye.
What is the stroboscopic effect?
If you look through previous physics books, you will find that people usually have a tendency called "visual persistence phenomenon", where we can continuously perceive things even if they no longer appear in front of us. We can see "persistent images" instead of a set of discrete static images.
Can strobe stop?
Stopping the strobe itself is very useless, however, the stimulating strobe effect is what we are trying to eliminate. Although eliminating the strobe effect is an incredible precision task, it can easily be reduced by adjusting the frame rate and shutter speed.
Except for the United States, AC power is provided at a frequency of 50 Hz, which means that the current will change 50 times between on and off within 1 second. By adjusting camera parameters such as shutter speed and frame rate to multiples or fractions of 50, the strobe effect can be significantly reduced.
Some LED lights are adjusted by the driver, and their flashing frequency is controlled by adjusting their switching cycle. If the flashing rate exceeds the camera frame rate, the strobe effect can be effectively eliminated.