1. What is Field of View Angle?

The field of view (FOV) angle is the angular extent of the observable world that is seen at any given moment through an optical instrument or by human vision. It's commonly used in photography, videography, optics, and vision science.

2. How Does the Calculator Work?

The calculator uses the field of view angle formula:

Where:

• \( \text{size} \) — The size of the object or sensor (in meters)
• \( \text{distance} \) — The distance from the observer to the object (in meters)
• \( \arctan \) — The inverse tangent function

Explanation: The formula calculates the angular size of an object based on its physical size and distance from the observer.

3. Importance of Field of View Calculation

Details: Calculating field of view is essential for designing optical systems, setting up cameras, understanding human vision, and many applications in physics and engineering.

4. Using the Calculator

Tips: Enter the size of the object or sensor in meters and the distance from the observer in meters. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between horizontal and vertical FOV?
A: Horizontal FOV is the angle along the width of the view, while vertical FOV is along the height. The calculation is the same but uses different dimensions.

Q2: How does FOV affect photography?
A: Wider FOV captures more of the scene (like wide-angle lenses), while narrower FOV magnifies distant objects (like telephoto lenses).

Q3: What is a typical human FOV?
A: Humans have about 120° vertical and 210° horizontal FOV with both eyes, though only about 60° is in sharp focus.

Q4: What units should I use for size and distance?
A: The calculator uses meters, but any consistent unit can be used (e.g., millimeters for both size and distance).

Q5: How does FOV relate to magnification?
A: Higher magnification typically results in a narrower FOV, as you're "zooming in" on a smaller portion of the scene.