This free resource was originally developed in early 2020 to support people who found themselves unexpectedly moving their work into virtual environments during the COVID-19 pandemic. It was updated in 2026 to reflect current smartphone technology and recording practices.

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VIDEO DOCUMENTATION WITH SMARTPHONES

Part III: Terminology Reference

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Camera terminology, demystified

What common camera settings change, and why you might care.

You do not need to control these settings manually to create useful video documentation. Most smartphones adjust them automatically. However, you may encounter these terms in your camera app, phone settings, or conversations about recording video. Understanding their practical effects can help you recognize why footage looks bright, dark, blurry, noisy, unusually colored, or different from what you expected.

Exposure: How bright or dark the image appears

Exposure refers to the overall brightness of an image. A properly exposed video retains visible detail in both the lighter and darker parts of the scene.

Smartphones usually set exposure automatically. You can often tell the phone which part of the image matters most by tapping your subject on the screen. Many phones then display a small sun or brightness control that allows you to make the image lighter or darker.

What this means for you: If your subject appears too dark or washed out, tap the subject and adjust the brightness before recording. Changing your position relative to a window or light source may improve the image more effectively than changing a camera setting.

Shutter speed: How sharp or blurred movement appears

Shutter speed is the amount of time used to capture each individual frame of video. It is commonly displayed as a fraction of a second, such as 1/30, 1/60, or 1/250. Some applications show only the bottom number.

A faster shutter speed, such as 1/250, can make movement appear sharper, but it also gives the camera less time to collect light. A slower shutter speed, such as 1/30, allows the camera to gather more light but creates more visible blur when the subject or camera moves.

What this means for you: Your phone may automatically use a slower shutter speed in a dim room, causing hands, bodies, or other moving subjects to look blurry. Adding light is often the best solution. For most classroom documentation, you can allow the phone to select shutter speed automatically.

Frame rate: How many images are recorded each second

Video is made from a rapid sequence of individual images called frames. Frame rate describes how many frames are recorded each second and is written as fps, or frames per second.

Common settings include:

  • 24 fps: Often associated with the appearance of film

  • 30 fps: A common general-purpose setting for smartphone video

  • 60 fps: Records movement more frequently and can make fast action appear smoother

  • 120 fps or higher: Usually intended for slow-motion recording

What this means for you: For most classroom documentation, 30 fps is a reliable choice. 60 fps may help when documenting fast movement, but it can create larger files and may require more light. Higher frame rates are most useful when you intend to slow the footage down later.

ISO: Brightness gained at the cost of image quality

ISO controls how strongly the camera amplifies the image signal it captures. Raising the ISO can make a dim scene appear brighter, but it may also introduce visible speckles, grain-like noise, reduced detail, and less accurate color.

A lower ISO generally produces a cleaner image but requires more available light.

What this means for you: If footage looks grainy or muddy, the phone may be compensating for low light by using a high ISO. Rather than changing ISO manually, first try adding light, moving closer to a light source, or repositioning the activity in a brighter area.

White balance: Whether colors look natural

Different light sources have different color qualities. Some lights appear warm and orange, while others appear cool and blue or slightly green. White balance tells the camera how to interpret the color of the available light so that white and neutral-colored objects appear natural.

White-balance settings may include symbols representing:

  • Daylight or full sun

  • Cloudy conditions

  • Shade

  • Incandescent or tungsten bulbs

  • Fluorescent lighting

Some camera applications express white balance as a number on the Kelvin scale, shown with the letter K. Lower Kelvin values describe warmer, more orange-colored light sources, while higher values describe cooler or bluer lighting conditions.

What this means for you: Automatic white balance is usually sufficient. If the color changes noticeably during a recording, the phone may be reacting to different light sources in the same room. Whenever possible, avoid combining strongly different sources, such as blue daylight from a window and orange light from a nearby lamp.

Focus: Which part of the image appears sharp

Focus determines which subject or area of the scene appears sharpest. Smartphones usually focus automatically and may continue changing focus as people or objects move.

Tapping a subject on the screen tells many phones where to prioritize focus. Touching and holding may lock the focus on some devices.

What this means for you: Before recording, tap the person, object, or demonstration that needs to remain clear. Avoid placing unrelated objects very close to the camera, because the phone may focus on them instead. Only lock focus when your subject will remain approximately the same distance from the phone.

Focal length: How wide or close the view appears

Focal length affects how much of the scene fits within the frame and how close or distant the subject appears.

Many smartphones contain several separate cameras, commonly represented by settings such as:

  • 0.5×: An ultra-wide view that captures more of the surrounding space

  • 1×: The phone’s standard camera view

  • 2×, 3×, or 5×: A narrower view that makes distant subjects appear closer

Each camera lens usually has a fixed focal length. Selecting another view may switch to a different physical camera, digitally crop the image, or combine both methods.

What this means for you: A wide setting can help capture a full classroom or a person’s entire body in a small space, but it may distort people or objects near the edges of the frame. A telephoto setting can make a distant subject appear closer, but it may require more light and steadier support. When possible, reposition the phone instead of relying heavily on zoom.

Aperture and f-stop: Light intake and background blur

Aperture is the opening inside a camera lens that allows light to reach the sensor. Its size is expressed as an f-number or f-stop, such as f/1.8, f/2.8, or f/8.

A lower f-number represents a wider opening. It allows in more light and can produce a shallower depth of field, meaning that the subject is sharp while the foreground or background appears blurred.

A higher f-number represents a smaller opening. It allows in less light but can help more of the scene appear acceptably sharp.

Most smartphone lenses have a fixed physical aperture that the user cannot change. Some Portrait or Cinematic modes offer an f-stop-style adjustment, but this usually controls digitally generated background blur rather than physically changing the lens opening.

What this means for you: For documentation, having the subject and surrounding activity clearly visible is usually more important than creating dramatic background blur. Standard video mode will generally be more reliable than Portrait or Cinematic modes, especially when documenting movement or several people.

Depth of field: How much of the scene appears in focus

Depth of field describes the range of distance that appears acceptably sharp. A shallow depth of field may keep one person sharp while blurring the background. A deeper depth of field allows subjects at several distances to remain more clearly visible.

Depth of field is affected by aperture, focal length, camera-to-subject distance, sensor size, and—in some smartphone modes—computational processing.

What this means for you: Smartphones naturally keep much of a scene in focus, which is often helpful for classroom documentation. Artificial background blur may struggle with moving bodies, hair, hands, props, or several participants, creating distracting visual errors.

Optical zoom and digital zoom: Two ways of making a subject appear closer

Optical zoom uses a camera lens with a narrower field of view to make a distant subject appear larger. On a smartphone, this often happens when the phone switches to a separate telephoto camera.

Digital zoom crops and enlarges part of the image. This can reduce detail and make softness, noise, and camera movement more visible.

Modern phones may combine optical lenses, sensor cropping, and computational processing, so the distinction is not always obvious to the user.

What this means for you: Use the phone’s marked camera options, such as 1× or 3×, rather than pinching far into the image. For the clearest result, move the camera closer whenever it is safe and practical.

Image stabilization: Reducing visible camera shake

Image stabilization helps reduce small movements caused by holding the phone. Smartphones may use physical movement inside the camera, digital processing, or a combination of both.

Stabilization can improve handheld footage, but it cannot fully correct large movements, sudden panning, or an unstable support.

What this means for you: Hold the phone with both hands, keep your elbows close to your body, move slowly, or use a tripod or stable surface. Stabilization works best as additional support—not as a substitute for steady filming.

The practical takeaway: Automatic settings are usually the best starting point. Good lighting, thoughtful camera placement, a stable phone, and a short test recording will improve your footage more reliably than changing advanced settings without a clear reason.