Calculator Input
Example Data Table
| Sensor | Focal Length | Distance | Horizontal View | Scene Width | Use Case |
|---|---|---|---|---|---|
| 1/2.8 inch | 2.8 mm | 10 m | 89.67 degrees | 19.89 m | Wide room coverage |
| 1/2.8 inch | 4 mm | 10 m | 69.70 degrees | 13.93 m | Entrance monitoring |
| 1/2.8 inch | 8 mm | 20 m | 38.41 degrees | 13.93 m | Gate or lane view |
| 1/1.8 inch | 12 mm | 25 m | 33.33 degrees | 14.96 m | Narrow detail view |
Formula Used
Horizontal angle: AOV = 2 × atan(sensor width ÷ (2 × effective focal length))
Vertical angle: AOV = 2 × atan(sensor height ÷ (2 × effective focal length))
Diagonal angle: AOV = 2 × atan(sensor diagonal ÷ (2 × effective focal length))
Scene width: width = 2 × distance × tan(horizontal AOV ÷ 2)
Scene height: height = 2 × distance × tan(vertical AOV ÷ 2)
Pixel density: pixels per meter = image width pixels ÷ scene width
Needed lens: focal length = sensor width × distance ÷ desired scene width
How To Use This Calculator
Select a sensor preset or choose custom dimensions. Enter the lens focal length from the camera data sheet. Add any multiplier for crop, extender, or digital lens mode. Enter the target distance, image resolution, mounting height, and downward tilt. Add object size if you want pixel coverage on a person, vehicle, or sign. Press the calculate button. Review the result table above the form. Use CSV or PDF export for documentation.
Overview
A CCTV camera angle of view calculator helps you select a lens before installation. It turns sensor size, focal length, and target distance into coverage values. The result shows horizontal view, vertical view, diagonal view, scene width, scene height, and pixel density. These values help compare wide, normal, and narrow lenses. They also reduce guesswork during site planning.
Why Angle Of View Matters
Angle of view controls how much area the camera can see. A short focal length gives a wide angle. It covers more ground, but objects look smaller. A long focal length narrows the view. It gives more detail on doors, gates, counters, or number plates. The best lens balances coverage with identification detail. Pixel density is important because a wide image may not hold enough detail. The calculator estimates pixels per meter at the selected distance. Higher pixel density gives better recognition.
Main Calculation Idea
The calculator uses trigonometry. It treats the sensor and lens as a right triangle. Half of the sensor sits opposite the lens focal length. The angle is doubled to get full field of view. Scene width is then found from the chosen distance. This method is common for rectilinear lenses. Strong fisheye lenses may not follow the same geometry. Digital zoom and crop factors can also change the effective focal length. That is why an effective lens multiplier is included.
Using Installation Values
Mounting height and downward tilt estimate ground coverage. The tool finds the center ground point, near limit, and far limit. If the vertical field reaches the horizon, the far limit is shown as unlimited. This is useful for wall, pole, and ceiling installations. Desired coverage width can also be entered. The calculator then estimates the lens needed for that target width.
Practical Planning Tips
Use real sensor dimensions when possible. Many cameras share similar lens names but use different sensors. Confirm resolution, aspect ratio, and lens type from the data sheet. Measure true distance to the target zone. Test the view on site when security risk is high. Lighting, motion blur, compression, and focus can reduce detail. Use the output as a planning guide, not a final guarantee. Keep exported results with the camera schedule for careful review.
FAQs
What is camera angle of view?
Camera angle of view is the visible angle captured by the lens and sensor. It can be horizontal, vertical, or diagonal. A wider angle covers more area but gives less detail per object.
Does focal length change the viewing angle?
Yes. A shorter focal length gives a wider view. A longer focal length narrows the view and increases detail on distant targets. Sensor size also affects the final angle.
Why does sensor size matter?
The sensor is part of the viewing triangle. A larger sensor with the same lens usually captures a wider view. A smaller sensor usually narrows the view.
What is pixel density?
Pixel density shows how many image pixels cover one meter of real scene width. Higher values usually improve detection and recognition. Low values may be fine for general monitoring.
Can this calculator handle varifocal cameras?
Yes. Enter the current focal length setting of the varifocal lens. For example, use 2.8 mm for wide mode or 12 mm for a narrow detailed view.
What does tilt angle mean?
Tilt angle is the downward aim from the horizontal line. It helps estimate near and far ground coverage. Very small tilt angles may create an unlimited far limit.
Are fisheye cameras supported?
This calculator is best for rectilinear lenses. Fisheye cameras use different projection geometry. Their real coverage should be checked with manufacturer data or field testing.
Why do exported results matter?
Exported results help document lens selection, coverage assumptions, and installation planning. They are useful for proposals, camera schedules, reviews, and later maintenance checks.