Editing Shutter speed (section)

==Cinematographic shutter formula==
{{further|Rotary disc shutter}}
Motion picture cameras used in traditional [[film]] [[cinematography]] employ a mechanical [[rotary disc shutter|rotating shutter]]. The shutter rotation is synchronized with film being pulled through the gate, hence shutter speed is a function of the [[frame rate]] and [[shutter angle]].

Where ''E'' = shutter speed (reciprocal of exposure time in seconds), ''F'' = frames per second, and ''S'' = shutter angle:<ref name=brown/>

: <math>E = \frac {F \cdot 360^\circ}{S}</math>, for ''E'' in reciprocal seconds

: <math>S = \frac {F \cdot 360^\circ}{E}</math>

With a traditional shutter angle of 180°, film is exposed for {{frac|48}} second at 24 frame/s.<ref name=brown>{{cite book | title = Cinematography: Theory and Practice : Imagemaking for Cinematographers, Directors & Videographers | author = Blain Brown | publisher = Focal Press | year = 2002 | isbn = 0-240-80500-3 | url = https://archive.org/details/cinematographyth0000brow | url-access = registration | page = [https://archive.org/details/cinematographyth0000brow/page/125 125] | quote = cinematography 360 shutter-angle shutter speed. }}</ref> To avoid effect of light interference when shooting under artificial lights or when shooting television screens and computer monitors, {{frac|50}}&nbsp;s (172.8°) or {{frac|60}}&nbsp;s (144°) shutter is often used.<ref>{{cite web|url=https://www.provideocoalition.com/shutter-speed-vs-shutter-angle/|title=Shutter Speed vs. Shutter Angle|last=Jeppsen|first=Matt|date=July 11, 2007|website=provideocoalition.com|url-status=live|archive-url=https://web.archive.org/web/20121113213201/http://provideocoalition.com/index.php/freshdv/story/shutter_speed_vs_shutter_angle|archive-date=November 13, 2012|access-date=December 5, 2019}}</ref>

Electronic video cameras do not have mechanical shutters and allow setting shutter speed directly in time units. Professional video cameras often allow selecting shutter speed in terms of shutter angle instead of time units, especially those that are capable of [[overcranking]] or [[Time-lapse photography|undercranking]].