That's your shutter, and be forewarned there's gonna be a lot of numbers, a lot of fractions.
So get your thinking hat on, let's do this.
Hey everyone, Camber here, welcome back.
Today we are talking about shutter speed and how it affects your video.
And if you're new here, this channel is all about teaching you how to use your camera
to make good videos, so if that's you, consider subscribing.
Before we get started, know that frame rate and shutter speed are NOT the same thing.
Your frame rate is the amount of individual frames recorded per second, whereas your shutter
speed is the length of time that each of those frames is exposed to light.
The shutter is a physical mechanism in front of your camera sensor that moves out of the
way to expose your sensor to light for a certain period of time and then moves back in front
of your sensor to stop the exposure of that frame.
And this controls how long the light hits your camera sensor.
So a longer exposure will result in more light hitting your camera sensor and a brighter
image, and a shorter exposure time will result in less light hitting the sensor and a darker image
The shutter speed is displayed on your camera as fractions of a second.
And since stops of light are based on a doubling or halving of the amount of light let in when
taking a photo or video, you can know exactly how any change in shutter speed will affect
your exposure because any doubling or halving of your shutter speed will result in a one-stop
change of light.
So if your current shutter speed is set to 1/400 of a second and you're on the "-1" on
your exposure meter, then changing your shutter speed to 1/200 of a second will result in
your exposure meter going to "0" because you divided your previous shutter by 2, which
would keep the shutter open twice as long and double the amount of light let in.
Conversely, if your shutter speed was set to 1/400 of a second and you were on the "+2"
on your exposure meter, then changing the shutter speed to 1/800 of a second would result
in the meter going to "+1" because you doubled the speed letting in half as much light.
You would then need to double the shutter speed again to 1/1600 of a second in order
to decrease by one more stop of light and bring your exposure meter to "0."
And aside from changing the length of time that light hits your sensor, the shutter speed
also has a stylistic effect in changing the motion blur of your images.
So with a very fast shutter speed, any motion in your shot gets frozen and looks very crisp;
but with a very slow shutter speed, any motion that's in your shot begins to get blurred.
And with photography you can choose any shutter speed you want depending on the style
you're going for, however with video you are much more limited.
The most common shutter speeds used in video are based on the 180 degree rule, which is
choosing a shutter speed that is doubled your frame rate meaning that you would use a shutter
speed of 1/60 of a second if you were shooting at 30 frames per second.
And as you'll find in many areas of video, many common practices come from the days of using film.
Film motion cameras used a physical rotary shutter where part of the shutter was a hollow
semicircle, and that's where the degrees came from.
During the first 180 degrees of rotation, the film was exposed, and during the second
180 degrees of rotation, the film was covered with no exposure to the film.
At this time the film was advanced to the next frame because film cameras need time
to physically move the film down for the next exposure, and because of this there couldn't
be shutter angles higher than 180 degrees for film.
The shutter then was limited to allowing an exposure time that was half that of the frame rate.
So if you could shoot at one frame per second, the shutter could only allow for half a second
of light with the shutter being at an angle of 180 degrees.
You could have shutter angles less than 180 degrees letting in less light, but this would
also change the look of your video.
And although current camera no longer control shutter speed using a rotary shutter anymore,
the shutter angle terminology has continued as a simple standard way of describing the
appearance of motion blur in video.
So let's take another look at the rotary shutter so we can look at some of the basic shutter
angles and determine how to calculate your shutter speed.
So we'll use 24 frames per second as our frame rate in these examples.
Since 360 degrees is the maximum exposure you can get, 360 will be your base number
and you'll divide any of the lower shutter angles into 360 and then multiply the result
of that by your frame rate to arrive at the shutter speed you'll need for that shutter angle.
So for a 360 shutter angle, 360 divided by itself would be 1.
So at 24 frames per second, you would get 1/24 of a second for your shutter speed.
Then at 180 degrees, that goes into 360 twice.
So then you would multiply your frame rate by 2 giving you 1/48 of a second for your shutter speed.
Going further for a 90 degree shutter angle, that goes into 360 four times.
So then you multiply your frame rate by 4 giving us 1/96 of a second.
Continuing on to 45 degree shutter angle, that goes into 360 eight times.
So we'll multiply 24 frames per second by 8, and that gives us our shutter speed for
a 45 degree angle at 24 frames per second.
Now, you're not gonna find these precise shutter speeds on DSLRs, so you'll just have to round
up to the closest one you can find.
But you get the idea on how to calculate your shutter speed for these various shutter angles.
But using a 360 degree shutter angle results in a slower shutter speed that gives a lot
more motion blur than you're used to seeing.
And using a 90 degree or 45 degree shutter angle results in a fast shutter speed giving
a series of crisp, choppy looking frames when played back that's usually referred to as
the cheap, video-y look.
Now, having crisp frames sounds like a good thing from a photography standpoint because
blurry frames typically look bad in a photo.
But if you take 24 of those, put them back-to-back and play them in one second, it starts to look pretty natural.
And the reason for that is because our eyes naturally see motion blur, which you can see
just from waving your hand around in front of your face.
Your hand doesn't look crisp throughout the movement; there's motion blur there.
And so the 180 degree shutter angle most closely resembles what we see naturally.
And of course to every rule there is an exception, and this is no different.
Other shutter angles can be used for effect.
If done carefully and well, they can enhance your story, and we'll talk about reasons to
use other shutter angles in a different video.
But for now to get your videos looking most like what you're used to seeing in movies,
using 24 frames per second as your base frame rate, just double that to 48; so round that
up to 1/50 and that'll be your shutter speed at 24 frames per second.
And if you're shooting at a higher frame rate, simply double that frame rate and then round
to the next closest number in order to get your shutter speed for that frame rate.
And that's all for shutter speed so if you made it this far, hit that like button and
let me know down below if you have any more questions about shutter speed.
It was a lot of numbers and angles and calculations, so if you are confused, let me know and
I'll help try to clear it up more down below.
Go ahead and subscribe if you haven't, and remember that the only way to get better at
something is to practice.
So get out there and film something.
See ya soon!
For more infomation >> How can your business use video? - Duration: 2:59. 
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