Field of View (FOV) Calculator
Calculated Field of View
What is Field of View (FOV)?
The Field of View (or Angle of View) in photography and videography defines the extent of the observable world that is seen at any given moment through a camera lens. It is determined by the relationship between the focal length of the lens and the physical dimensions of the camera sensor.
The Mathematics of FOV
To calculate the angle of view, we use the following trigonometric formula:
α = 2 × arctan(d / 2f)
- α is the angle of view in degrees.
- d is the dimension of the sensor (width, height, or diagonal).
- f is the effective focal length of the lens.
Common Sensor Sizes Reference
| Sensor Type | Dimensions (mm) | Crop Factor |
|---|---|---|
| Full Frame | 36.0 x 24.0 | 1.0x |
| APS-C (Nikon/Sony) | 23.6 x 15.6 | 1.5x |
| APS-C (Canon) | 22.2 x 14.8 | 1.6x |
| Micro Four Thirds | 17.3 x 13.0 | 2.0x |
Why Calculation Matters
Understanding FOV is crucial for architectural photography, landscape work, and surveillance planning. For example, a 50mm lens on a Full Frame camera provides a 39.6° horizontal view, which is considered "normal." However, placing that same 50mm lens on a Micro Four Thirds sensor reduces the horizontal view to just 19.7°, effectively making it a telephoto lens.
Practical Example
If you are using a 24mm wide-angle lens on a Full Frame sensor (36mm width):
Horizontal FOV = 2 × arctan(36 / (2 × 24)) = 73.7°
This wide perspective is ideal for capturing vast landscapes or tight interior spaces where you cannot physically move further back from the subject.