What's SHUTTER ANGLES & CREATIVE CONTROL??

As DP we need know our cameras

CONCEPT

The “shutter angle” is a useful way of describing the shutter speed relative to the frame rate. The term is a conceptual relic of rotary shutters, where a disc with an angled opening would spin and let in light once per revolution to expose each frame. The larger the angle, the slower the shutter speed—all the way up to the limit of 360 degrees, where the shutter speed could become as slow as the frame rate. At the other extreme, the shutter speed can be made arbitrarily fast by decreasing the angle.

Although current cameras don’t necessarily control shutter speed in this way, the shutter angle terminology has persisted as a simple and universal way of describing the appearance of motion blur in video. If one wants subjects which are blurred for a greater fraction of their frame to frame displacement, then one would choose a larger shutter angle, and vice versa:

By far the most common setting for cinema has been a shutter angle near 180 degrees, which equates to a shutter speed near 1/48 of a second at 24 fps. Any larger, and motion appears more smeared since the end of blur in one frame extends closer to the start of blur in the next frame. Any smaller, and the motion appears more stuttered and disjoint since the blur gap increases, causing frames to become more like discrete images.

Although many film cameras were capable of only certain shutter angle ranges, digital is providing many exciting new possibilities. Just as focal length and aperture have been used as creative tools for controlling sense of scale and depth of field, shutter angle has the potential to do the same for motion.

The optimum setting will ultimately depend on other factors, such as the speed of subject movement within the frame, or the creative intent of the cinematographer. For example, one might wish to use a larger shutter angle to increase the exposure time and reduce image noise in low-light, or to give the impression of softer and more fluid motion. Alternatively, with fast action one might place more importance on depicting crisp details in each frame by using a smaller shutter angle.

Another consideration might be the film era one desires to emulate. Shutter angles much less than 180° more closely mimic the style of old 1950’s news reels, for example, and a shutter angle of 180° will typically give footage a standard cinematic style.