The Slow Mo Guys are well-known for creating fascinating slow motion videos of various things on youtube. Their latest video is a super slow motion of a shutter inside a DSLR camera.
Along with your aperture, shutter speed controls the amount of light you let in your camera. If you ever wonder why your photos are coming out blurry indoors or at night, it is due to a slow shutter speed. You camera is trying to let in more light by leaving the shutter open longer. You can read more about that here or here.
Watch this video and you’ll now know what’s happening inside your camera when you press that shutter button.