October 25, 2014 at 7:02PM

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What's the deal with shutter angle?

Can someone please explain exactly what the shutter angle is, what it is you change in an image when you adjust the shutter angle, and why a dop might choose to alter it rather than colour temp, aperture, or shutterspeed? Please and thank you! :)

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So the shutter angle is in fact a really angle. In the old days of film it was needed to have a working optical view finder (OVF) while recording. Basically it was a half disc between lens and film that has a mirror which could reflect the light to the OVF like a DSLR mirror. But instead of a flipping mirror in a DSLR the shutter angle disc was rotating so it lets through light to the film and also reflects some to the OVF.

Make this 24 time a second you have 24 fps. And every frame is exposed with 1/48th of a second because the shutter angle was mostly 180 degrees which is exactly a half disc. There are also shutter angles with 90 degrees (3/4 of a full disc), 45 degrees (7/8 of a full disc) and 270 degrees (1/4 of a full disc) in film.

This is influencing the shutter speed of your camera of course. In early days they found out that 180 degrees perform best with motion blur. This is also the reason why you shoot with 1/50 at 25 fps or 1/60 at 30 fps because this is 180 degree shutter angle.
Nowadays digital cameras don't need this anymore because the expose electronical. But most cameras keep this system instead of shutter time in seconds because it has the advantage that you don't have to worry about your shutter speed if you change your framrate because it stays always at 180 degrees (or whatever your've choosen). Today you can also go from about 11.25 to about 359 degrees. Their really shutter speeds depend on the framerate.

So if you are working with a camera that works with shutter angle most of the time you will be fine if you are using 180 degrees. If you want a faster shutter lower the shutter angle. If you want a slower shutter rise the shutter angle.

If you want to know what real shutter your shutter angle is you can calculate this with this formula:

((360/) * )^(-1) =

February 11, 2016 at 6:42AM, Edited February 11, 6:43AM

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Eric Halbherr
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