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Sometimes the most intimidating part of making a movie is that little box of concentrated technology called "The Camera." But, FEAR NOT! In this episode of Crash Course Film Production, Lily helps us dissect the basics of modern movie cameras so you can have an easier time getting started... hopefully!

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  Intro (0:00)

Hey, you! Yeah, I'm talking to you. But I'm actually talking to a camera.

A camera is a collection of parts that can help you tell a visual story. It takes in light through a lens and captures images, creating that illusion of reality we keep talking about. You could even use your cell phone camera to make a movie!

But filmmakers usually have equipment that gives them a lot more control. So, let's look through the eyes of a cinematographer and see how they combine camera technology and the language of film to get that perfect shot.

[Opening music]

 How the Camera Works (0:39)

Let's start with the tool that focuses light into a camera: the lens. Some cameras have a lens that's permanently attached, but others have a separate body with a lens mount, where you can swap out different lenses for more creative control. 

For instance, low-budget filmmakers can rent great lenses for cost-effective cameras to improve their footage quality. Or they might user older lenses to make a period piece feel more authentic.

All lenses have either a fixed of variable focal length, which is the distance from the center of the lens to where the image is in focus. And focal length determines your field of view, which is how much you can see in the frame. It's usually measured in millimeters, and a 50mm lens is generally thought to be closest to how our eyes frame the world. 

A fixed focal length lens can be called a prime lens. It tends to have higher quality glass because it's specialized for just one focal length. On the other hand, a variable focal length lens is more versatile. It's also called a zoom lens, because it can zoom in and out. 

Now, you can also control how much light gets into the camera body through a hole called the aperture. It works like the iris and pupil in your eye, becoming wider or narrower to let more or less light through the lens. Aperture is measured in f-stops. That lowercase "f" stands for focal length, because it's the ratio of the focal length compared to the diameter of the aperature. 

An f/1.2 lens, for example, can open wider than an f/5.6. So, when you "stop down" your aperture, you're making that diameter of the opening smaller, letting less light in, and changing that ratio. But, as you stop down, you'll notice that the number is actually getting larger. 

And to control how long the film or sensor inside is exposed to light, you can adjust the camera's shutter speed. You can think of a typical shutter as a door in the lens that opens and closes really quickly. If you have an aperture that can open wider, like in a f/1.2 lens, you can let more light in, and have a faster shutter speed. 

Usually your shutter speed is about double your frame rate. So if you're shooting 24 frames per second, for instance, your shutter speed would be 1/50 of a second.

But there's one little problem with shutters that work like a door: they click. Which can get noisy. So on some movie film cameras, you'll have a shutter angle instead of a shutter speed. These shutters are rotary discs that spin, to control the amount of light that enters an opening into the camera. A small shutter angle works like a faster speed: the image will be exposed more quickly, and it'll look crisper.

With a larger shutter angle or slower shutter speed, the image will be smoother and have more blur from any motion. 

How light gets turned into an image depends on what kind of camera you're using. In a film camera, the light hits the chemical-coated film strip at an opening called the gate, which exposes it so it retains an image.

In a digital camera, the light heads to an electronic sensor, which translate the light energy into a digital image. The camera that's filming me right now has what's called a Complementary Metal Oxide Semiconductor, or CMOS, sensor. Other digital cameras might have a Charged Coupled Device, or a CCD, which uses more power, but produces better images than earlier CMOS sensors. 

Both film and digital sensors also have a property called ISO. The higher the ISO number, the more sensitive they are to light. The name comes from the International Standards Organization, which created the scale filmmakers use. 

Generally, the lower your ISO, the cleaner and richer your images will look. But, if you're in a room without a lot of light, your image will be pretty dark. In this case, it's tempting to just bump your ISO way up to like 1600, to increase sensitivity to available light.

You've gotta be careful with that, though. Depending on the camera or film stock, raising the ISO to compensate for low light just brightens everything in frame, and can result in grainy, lower-quality footage. So, instead of raising your ISO, you might wanna add more light to the scene and open the aperture to allow as much of it in as possible. 

Now, imagine you've put everything we've talked about to use. You've adjusted your lens, aperture, shutter speed, and ISO, and captured some beautiful footage. All that footage is stored on what's called the media.

In a film camera, the media is the film itself. As long as you don't lose or ruin it, you'll always have what you shot. In a digital camera, the media is a data storage device like tape, drives, or cards. And you'll have to decide on a codec. 

"Codec" is a portmanteau of "coder" and "decoder." Because that's what it does. It's a program that can compress what the camera has shot onto your storage device, and then decompress that footage when you need to work with it in post-production. 

Basically, it's like a little package of digital information. You might recognize a codec like H.264. Or mp3! Shooting in raw means the images don't get packaged or processed. You get higher quality footage, but you need a bunch of storage because those image files get huge. 

 The Camera Operators (4:38)

Now, understanding how a camera works is only part of a filmmaker's job. Film sets have an entire team of talented artists working to create the visual story of a movie. The Director of Photography, or cinematographer, is the head of the camera department. They create the shot list with the director, to plan how everything in the screenplay will be captured visually. 

The camera operator is the person who actually controls the camera and frames the shots. Sometimes you need a static shot, so the camera operator uses a tripod. The cool kids call this a camera "on sticks." 

Or sometimes, you want a moving shot, so the operator uses a handheld camera, or attaches one to a mechanical cart called a dolly. There's also a device called a Steadicam, which makes a shot smoother than handheld, but not as smooth as a dolly. 

Now, the person who manages all this equipment and sets up the camera is the First Assistant Camera, or 1st AC. They work under the main camera operator. Sometimes, you'll hear this job referred to as Focus Puller because the 1st AC controls the camera lens to focus on the action through the scene.

It might sound simple, but for decades focus pullers couldn't look through the camera lens while doing their job, because the camera operator was looking through the lens. Nowadays, the 1st AC will usually have a monitor, but they also have to rely on detailed marks from rehearsal and a whole lot of skill. 

The 2nd AC takes all the camera notes for each shot and operates the slate, or clapper, to mark each scene. Ooof, soft sticks. They also haul equipment around, from cameras to media. 

If you're shooting on film, a 2nd AC is the film loader, who changes the camera magazines with rolls of film inside. And if you're shooting digital, the 2nd AC is responsible for getting any storage devices to the Digital Imaging Technician, or DIT, who manages all the media. 

  The Language of Film (6:06)

Now, you might understand all the nuts and bolts of a camera, but it's all for nothing if you're not using these tools to tell a story. Making the audience feel something because of moving pictures - that's what makes movies magic! 

From a voyeur shot through a window in a horror movie, to the subtle push on the love interest in a melodrama, there's a language and an artistry to framing, angles, and camera movements.

Take the rules of thirds, which is a general way to think about composing a frame. The idea is to divide it up into vertical and horizontal thirds, and then stick what you want people to focus on where those lines intersect. 

What or who dominates a frame can affect how an audience views a scene. And what's in or out of focus can steer our attention even more.

For instance, in the film Road to Perdition, the cinematographer Conrad Hall combined these storytelling tools really beautifully. In one scene, a character played by Daniel Craig is dominating the frame, but the other two men walking away from him, played by Paul Newman and Tom Hanks, are the ones in focus.

So our attention is on Daniel Craig's character because he's front and center in the scene. But because the other men are kept in focus, we can feel that he's thinking about them - all through visual storytelling. 

Even if you can compose what looks like the perfect frame, it's important to remember that cameras aren't static! Camera movements have their own language, too. A push is when the camera is literally pushed closer to the action in a scene. It's like we're leaning in, and builds intensity. 

And a pull is the opposite! The camera physically moves back. This could reveal something that we didn't see before, or help us leave a scene and lessen our connection. 

Pushes and pulls are often achieved by using a dolly to move the camera closer and farther from the action. They have a different look to them than just changing the focal length of a zoom lens. if you want to get really fancy, you can use a tracking shot to move the camera with your actors, like by moving a camera on a dolly parallel to the action. 

Now, even how a camera is set up can affect the visual storytelling in a movie. A camera on a tripod is "locked down" and can make a scene feel safe and stable, like when a character who craves adventure is sitting at home in their regular life. But when they're introduced to whatever's going to rock their world, and jump up, the camera might move too. 

On the other end of the spectrum are handheld cameras. Think of those horror movies with shaky cameras - they're harder to see and understand, but feel more chaotic and unstable.

The real job of the camera is to capture visuals that let us enter the worlds of movies, and feel what the characters feel. Knowing how a camera works can help strengthen your storytelling, but a lot of it comes down to becoming fluent in the language of film. And that, like all of these jobs, comes with a ton of practice. 

  Review and Credits (8:20)

Today, we talked about the guts of the camera and how they come together to make a versatile piece of equipment. We learned about the positions in the camera crew, and how the poetry of framing, angles, and camera movement are what make it a powerful storytelling tool. And next time, we'll talk about the counterpart to the camera's visuals: sound. 

Crash Course Film Production is produced in association with PBS Digital Studios. You can head over to their channel, check out a playlist of their latest shows, like Shank's FX, The Art Assignment, and It's Okay to Be Smart. This episode of Crash Course was filmed in the Dr. Cheryl C. Kinney Crash Course Studio with the help of all these nice people. And our amazing graphics team is Thought Cafe.

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