The Focal to Lens Angle Calculator helps you find the angle of view based on your camera’s sensor size and the focal length of the lens. This tool is crucial for photographers and videographers who want to know how wide or narrow a scene will appear when viewed through a specific lens.
This calculator belongs to the Camera Lens / Photography Tools category. It's especially useful for:
- Landscape photographers wanting wide angles
- Portrait photographers managing background compression
- Videographers planning framing on different sensors
By knowing the exact angle, you can choose the right lens for your subject, location, and visual style.
Formula of Focal To Lens Angle Calculator
The angle of view (θ) can be calculated using the following:
Where:
- θ = Angle of view in degrees
- d = Sensor dimension in millimeters (width for horizontal, height for vertical, diagonal for total)
- f = Focal length of the lens in millimeters
Common Use Cases:
- Horizontal Angle of View: Use the sensor width
- Vertical Angle of View: Use the sensor height
- Diagonal Angle of View: Use the sensor diagonal, which is calculated by:
Sensor Diagonal = √(width² + height²)
Understanding these variations helps you frame scenes accurately depending on orientation.
Sensor Size Reference Table and Related Calculations
| Sensor Type | Width (mm) | Height (mm) | Diagonal (mm) | Notes |
|---|---|---|---|---|
| Full Frame (35mm) | 36 | 24 | 43.27 | Standard reference |
| APS-C (Canon) | 22.3 | 14.9 | 26.82 | Crop factor ~1.6 |
| APS-C (Nikon/Sony) | 23.6 | 15.6 | 28.21 | Crop factor ~1.5 |
| Micro Four Thirds | 17.3 | 13.0 | 21.64 | Crop factor ~2.0 |
| 1-Inch Sensor | 13.2 | 8.8 | 15.86 | Crop factor ~2.7 |
This table gives quick reference values that you can plug directly into the angle of view formula for fast results.
Example of Focal To Lens Angle Calculator
Scenario: You’re using a 50mm lens on a full-frame camera and want to calculate the horizontal angle of view.
Step 1: Identify sensor width for full frame = 36 mm
Step 2: Focal length = 50 mm
Step 3: Use the formula:
θ = 2 × arctangent(0.36)
θ ≈ 2 × 19.8 ≈ 39.6 degrees
Conclusion: The horizontal angle of view is approximately 39.6° on a full-frame sensor using a 50mm lens.
Most Common FAQs
The angle of view is the width of the scene that your lens captures. It's affected by the lens focal length and the camera's sensor size.
They’re related but not identical. Angle of view is a theoretical value based on geometry. Field of view is what you actually see, which can also be influenced by lens distortion and cropping.
A smaller sensor only captures a smaller portion of the image circle projected by the lens, which narrows the angle of view and gives a zoomed-in effect.