The bird did not flap its wings, but was still floating in the air. What phenomenon happened? The answer turned out to be surprisingly simple.
Recently, a video is really “breaking the virtual world”, attracting a lot of views and shares on social networking sites.
This video was cut from a CCTV (security camera) in front of an apartment, recording a bird passing through the camera. But the problem is that the bird flies without flapping its wings, just like floating in the air.
With such a mysterious scene like this, the video has received the attention of a large number of netizens. Most believe that the video has been edited. However, the real answer lies in the camera’s own recording capabilities.
The bird flew without flapping its wings, just like floating in the air.
Each camera will record with 2 criteria: with shutter speed (shutter speed – time to capture light when active) and frame rate per second (FPS). The faster the shutter speed, the more realistically fast moving images will become on screen (and vice versa). The FPS rate indicates the number of images captured per second.
In this case, the FPS rate almost perfectly coincides with the bird’s wingspan. Along with the shutter speed is too fast, the bird in the video will no longer flap its wings, but float as we have seen.
The human eye itself can also cause this phenomenon – known as the “chariot-wheel illusion”. The proof is that when looking at the wheels going too fast, we will feel like the wheels have stopped, no longer turning even though the car is still running.
Basically, this phenomenon stems from the brain’s inability to recognize consecutive images , because humans cannot observe every moment of a movement. Although with still images, the eye can capture up to 200 FPS, but when moving, the number drops to just 13.
So how about the rest of the photos? The brain simply “fills in the blanks”. In the case of the wheel, the brain randomly picks up a few images in motion, and that’s why you see the wheel stationary, or spinning slowly, or even spinning in the opposite direction. transfer.