Field of view is the difference between seeing everything and seeing nothing.
You've probably seen CCTV footage where the action happened just outside the frame. The camera was too narrow. Or footage where the subject was so small you couldn't identify anyone. The camera was too wide. That's what field of view is all about — how much area a camera captures.
This guide explains field of view in simple terms, and why it matters more than megapixels when it comes to actually catching criminals.
What is Field of View (FOV)?
Field of view is the width and height of the area a camera can see, measured in degrees. A wide field of view (e.g., 90° or more) captures a broad area but less detail. A narrow field of view (e.g., 30° or less) focuses on a small area with more detail — like a hallway or a gate.
The field of view is determined by the lens focal length. Shorter focal lengths (2.8mm, 4mm) give wide angles. Longer focal lengths (12mm, 50mm) give narrow, zoomed-in views.
Wide vs Narrow Field of View
Wide Angle (90°+)
Best for: large compounds, parking lots, open areas where you need general coverage.
Narrow Angle (30°)
Best for: gates, doorways, corridors, and choke points where you need clear identification.
Common Lens Sizes and What They See
| Lens Size | Field of View | Best For |
|---|---|---|
| 2.8mm | ~100° (very wide) | Large rooms, open compounds |
| 4mm | ~80° (wide) | Driveways, parking, general home coverage |
| 6mm | ~50° (medium) | Gates, doorways, small rooms |
| 12mm | ~25° (narrow) | Long corridors, specific choke points |
| 50mm+ | ~10° (very narrow) | License plate capture, long-distance zoom |
*Approximate values. Actual field of view varies by sensor size and manufacturer.
Placement is More Important Than Megapixels
An 8MP camera with the wrong field of view is worse than a 2MP camera with the right field of view. If the camera can't see the area where incidents happen, resolution doesn't matter. If the camera sees too much, the subject becomes too small to identify.
That's why we always recommend a free site survey. We assess your property and choose the right lens and placement for each camera location.
Get the right camera angles for your property.
Book a free site survey. We'll assess your compound and recommend the right lenses and placement — no guesswork.
📋 Book Free SurveyOr call: 0722 625 525
Frequently Asked Questions
For a gate, we usually recommend a 4mm to 6mm lens. This gives you enough width to see the gate and approaching visitors while still maintaining clear detail.
Not exactly. The camera resolution stays the same, but the subject appears smaller. For general coverage, wide is good. For identification, you want a narrower angle.
Some cameras have varifocal lenses that allow you to zoom in and out. Others have fixed lenses that require replacing the camera. We can advise during installation.
A 2.8mm or 4mm lens works well for general parking lot coverage. If you need license plate capture, a dedicated 12mm or varifocal camera is better.
Both types can have the same lens options. The shape of the camera doesn't determine field of view — the lens does.