Words for capturing images
Cameras of every kind rely on the same few ideas, and photographers and video makers use many shared words. Below is a plain explanation of common terms, grouped by what they help you do: capture light, frame a shot and finish the footage. Settings and menus vary by camera, so use these as concepts rather than as instructions for any one device.
Light and exposure
Exposure. How much light reaches the camera’s sensor, which determines how bright or dark the image appears. An overexposed image is too bright and loses detail in the lightest areas. An underexposed image is too dark.
Aperture. The adjustable opening in a lens that lets light in. It is written as an f-number, such as f/2.8. A smaller number means a wider opening, which lets in more light and usually makes the background blurrier.
Shutter speed. How long the sensor is exposed to light. A fast shutter speed freezes motion; a slow one lets motion blur. In video, shutter speed is often tied to frame rate.
ISO. The sensor’s sensitivity to light. Higher values brighten an image in dim conditions but usually add visible grain or noise.
Exposure triangle. A name for the way aperture, shutter speed and ISO work together to set exposure.
Depth of field. How much of the scene, front to back, appears sharp. A shallow depth of field keeps just the subject sharp.
Focal length. A lens measurement, in millimeters, that affects how wide or narrow the view is. Short focal lengths give a wide view; long ones appear to zoom in.
White balance. An adjustment so that colors look natural under different kinds of light. Wrong white balance can leave a warm orange or cool blue cast. Understanding natural light helps you judge it.
Histogram. A graph showing how the brightness values in an image are distributed, used to check exposure.
Dynamic range. The span between the darkest and brightest parts of a scene that a camera can capture with detail.
Highlights, shadows and midtones. The brightest, darkest and in-between areas of an image.
Framing and composition
Composition. How elements are arranged within the frame. Image composition guidelines, like the rule of thirds, are starting points rather than laws.
Rule of thirds. Imagining the frame divided into a three-by-three grid and placing key elements along the lines or intersections.
Aspect ratio. The proportion of the frame’s width to its height. Common ratios include 16:9 for widescreen video, 4:3, and 1:1 for squares. Vertical formats such as 9:16 are common for phones.
Shot size. How much of a subject the frame includes. A wide shot shows the surroundings, a medium shot shows a person from about the waist up, and a close-up fills the frame with a face or object.
Angle. The camera’s position relative to the subject, such as eye level, high or low.
B-roll. Supplementary footage that covers or illustrates the main footage, such as hands working while a person talks. The main footage is often called A-roll.
Establishing shot. A wide shot that shows where the action happens.
Shot list. A planned list of the shots you need. A shot list keeps a shoot organized.
Storyboard. A series of sketches showing how shots will look in sequence.
Cutaway. A shot of something other than the main action, used to break up an edit or hide a cut.
Motion and video
Frame rate. The number of still frames shown per second, written as fps. Cinema has traditionally used 24 fps. Many broadcast and web standards use 25, 30 or 60 fps, and the best choice depends on your delivery format. Higher rates can make motion look smoother; they can also be used to create slow motion.
Slow motion. Footage recorded at a high frame rate and played back at a normal rate, which stretches the action.
Resolution. The number of pixels in the image, such as 1920 by 1080. More pixels can mean more detail, but also larger files.
Bitrate. The amount of data used per second of video. Higher bitrates usually keep more detail but create larger files.
Codec. A method of compressing and decompressing video. Different codecs trade off quality, file size and compatibility.
Container (file format). The wrapper that holds video, audio and other data in one file, such as the type shown by the file extension. This is separate from the codec inside. Choosing image formats follows similar trade-offs for photos.
Stabilization. Reducing shaky motion, either in the camera or in software. Camera stability can also come from technique.
Rolling shutter. A distortion in some cameras where fast movement looks skewed or wobbly because the sensor reads the image line by line.
Editing and finishing
Timeline. The workspace in editing software where clips are arranged in order.
Cut. An instant change from one shot to the next.
Transition. A visual effect between clips, such as a dissolve.
Trim. Shortening a clip by changing its start or end point.
Color correction and color grading. Correction adjusts exposure and color so footage looks natural and consistent. Grading is a creative choice that gives footage a particular look.
Proxy. A smaller, lighter copy of high-resolution footage used to make editing run more smoothly.
Render and export. Producing a finished file from an editing project.
Captions and subtitles. On-screen text for spoken words. Captions generally also describe important sounds. See video captions for how they help viewers.
Lower third. On-screen text, usually in the lower part of the frame, that names a person or topic.
Choosing what to learn first
If you are new, exposure, aspect ratio and frame rate are the three ideas worth understanding before the rest. Aim to learn the others when a project needs them, and expect that results will vary by equipment and conditions.