What is video
A video is a series of photographs that go by so fast your brain stitches them together into movement. Understanding that changes how you shoot: how many pictures per second, how big, and what shape.
A video is lots of photos in a row
Each still image in a video is called a frame. When frames go by fast enough, around 16 or more per second, the eye stops seeing separate pictures and perceives continuous movement. Cinema has been running at 24 frames per second for almost a century.
This has a practical consequence you'll see throughout the course: every frame is a little photograph with its own exposure, focus and framing. Everything you know about photography applies, but repeated many times per second and with something photography doesn't have: time.
Frames per second (fps): what to choose
The fps (frames per second) setting tells you how many images are recorded every second. There's no "best" number: each one gives a different feel.
| fps | Feel | When to use it |
|---|---|---|
24 / 23.976 | Cinematic, with a slight motion "judder" | Fiction, short films, videos with a film look |
25 | Very similar to 24 | TV standard in the UK and Europe (PAL). The safe choice for everything there |
30 / 29.97 | A little smoother | Standard in the US and Japan; many phones record this way by default |
50 / 60 | Very smooth, "live TV" look | Sports, video games, or to slow down to half speed |
100–240 | Slow motion when played back at 24, 25 or 30 | Spectacular moments: water, jumps, hair in the wind |
If you're not sure what to pick, match your local power grid: shoot at 24 or 30 fps in the US (60 Hz power) and 25 fps in the UK and Europe (50 Hz). That way you avoid flickering lights and fit in with TV and almost any project.
Real slow motion
Slow motion isn't achieved by "stretching" the video in the edit: it's achieved by recording more frames than you're going to play back. If you shoot at 50 fps and play back at 25, every real second lasts two on screen, with no stutter. If you stretch a 25 fps video, the software has to invent frames, and it shows.
| You shoot at | You play back at | Result |
|---|---|---|
| 50 fps | 25 fps | 50% speed (2× slower) |
| 100 fps | 25 fps | 25% (4× slower) |
| 120 fps | 24 fps | 20% (5× slower) |
| 240 fps | 24 fps | 10% (10× slower) |
Resolution: how many pixels each frame has
Resolution is the size of each frame in pixels. More resolution means more detail and more room to crop in the edit, but also heavier files and a computer that struggles more.
| Name | Pixels | What for |
|---|---|---|
| HD (720p) | 1280 × 720 | Almost obsolete now |
| Full HD (1080p) | 1920 × 1080 | Enough for social media and most web videos |
| 4K UHD | 3840 × 2160 | Today's standard: lets you reframe and deliver in Full HD with extra sharpness |
| 4K DCI | 4096 × 2160 | Digital cinema |
| Vertical Full HD | 1080 × 1920 | Reels, TikTok and Shorts |
The p in 1080p stands for progressive: each frame is recorded whole. If you see an i (1080i, interlaced), that's an old TV system best avoided.
Shooting in 4K and editing on a Full HD timeline gives you up to 2× digital zoom without losing quality. From a single medium shot of an interview you can also get a close-up. It's one of the most common tricks in social media and interview videos.
Aspect ratio: the shape of the rectangle
Aspect ratio is the proportion between the width and height of the image. It decides much more than size: it decides what fits in the frame and how you compose.
Think about the format before you shoot. If the video will end up vertical, frame for vertical or leave space at the sides to crop later. Cropping 16:9 down to 9:16 leaves you with less than a third of the image.
File format: container and codec
A video file has two layers that often get mixed up:
- The container is the box:
.mp4,.mov,.mxf. It defines how picture, sound and metadata are stored together. - The codec is the compression method for what's inside: H.264, H.265 (HEVC), ProRes, DNxHR, AV1…
Two .mp4 files can behave very differently if one is H.264 and the other H.265. You'll see this in depth in the exporting lesson. For now, remember this: camera codecs (H.264/H.265) save space but are harder to edit; editing codecs (ProRes, DNxHR) take up a lot of space but play back smoothly.
Bitrate: the amount of data per second
Bitrate is measured in megabits per second (Mbps) and tells you how much information is stored every second. With the same codec, more bitrate means more quality and more gigabytes. You can work out how much space a recording will take with the bitrate calculator.
- A video is a series of frames: 24 or 25 per second gives a film feel.
- 24 or 30 fps is the safe choice in the US, 25 fps in the UK and Europe; double that if you want to slow things down.
- 4K gives you room to spare; Full HD is enough for social media.
- Decide the aspect ratio before you shoot.
- Container (.mp4) and codec (H.264) are different things.
Your turn: your first frame rate test
Record the same movement (someone walking or water falling) three times: at 25 (or 30), at 50 (or 60) and, if your camera or phone allows it, at 120 fps.
- Import the three clips into a 25 fps timeline (30 fps if you shot at 30/60).
- Slow the 50 fps clip down to 50% and the 120 fps clip to 20% (or 25% on a 30 fps timeline).
- Also duplicate the 25 fps clip and slow it down to 50%. Compare: can you see the stutter?
Frequently asked questions
Is it better to shoot at 24 or 25 fps?
The visual difference is tiny. In the UK and Europe, 25 fps avoids flickering lights and fits with TV; in the US, 24 or 30 fps does the same job with 60 Hz power. 24 fps is the cinema standard. What matters is not mixing frame rates in the same project.
Do I need to shoot in 4K?
It isn't essential. Full HD is enough for most web videos, but 4K gives you room to reframe and stabilize without losing sharpness.