Filming & Production
Shutter angle
Also called: shutter degrees
The number comes from the rotating disc in a film camera, where a 180 degree opening exposed each frame for half the time it sat in the gate. Translated to digital, the shutter speed works out at one over twice the frame rate. Shoot 24fps at 180 degrees and you are at 1/48. Shoot 60fps and you are at 1/120.
The advantage over setting shutter speed directly is that the angle stays correct when frame rate changes. Set 180 degrees once and slow motion, normal speed and everything in between carry consistent motion blur. Go narrower, down towards 45 degrees, and movement takes on the stuttering look used in battle scenes.