Magic trick or science? Helicopter appears to ‘float’ towards the ground on camera

Science can explain many mysteries that we come across in our everyday lives. But seeing a helicopter ‘float’ towards the ground without any of its blades moving is not an everyday mystery. Yet science can also explain this strange phenomenon. A Twitter account posted a short video of a helicopter slowly flying overhead as it approached lower and lower. However, in the video, the blades of the helicopter did not appear to move at all. As helicopters fly using their two sets of rotors, the flight of the helicopter seems improbable. Thankfully for many other confused Twitter users, the account did post an explanation of what was being observed. “When the rotation speed of the helicopter propeller matches the number of images per second (fps speed) of the camera,” the original post said.

This common visual illusion happens when the shutter speed of a camera matches up with the rotational speed of an object that it is filming. This results in the rotating object appearing to be completely still in the video. This effect also happens when the rotating object and the shutter speed sync up and don’t exactly match. A sync happens when the speeds are in multiples of each other. The shutter speed of a camera is the time that the digital sensor inside a camera remains exposed for capturing light. A shutter speed of 1/2 means that the shutter remains open for half a second which creates more motion blur while faster shutter speeds like 1/2000 only see exposure for just one-two-thousandth of a second. Most cameras tend to shoot at 1/50 or 1/60 shutter speed to give smooth 24 frames per second or 30 frames per second video. Read all the Latest News , Trending News ,  Cricket News , Bollywood News , India News and Entertainment News here. Follow us on Facebook, Twitter and Instagram.