Glossary: Field of View (FOV)

What is Field of View (FOV)?

Field of View (FOV) refers to the extent of the observable area that a camera, trail camera, or optical device can capture at a given moment. Usually expressed in degrees, FOV determines the width and breadth of the scene visible through the device’s lens. A wider FOV encompasses more of the environment, while a narrower FOV focuses on a smaller, more specific area.
In trail cameras, the choice of FOV can significantly impact overall effectiveness, making it a crucial factor when selecting a camera for specific use cases, such as wildlife monitoring or security.

Key Characteristics of Field of View

• Definition: The measurable angle or extent of the observable scene visible to the camera lens.
• Measurement Units: Expressed in degrees (e.g., 60°, 100°).
• Types:
  • Horizontal FOV: The extent of the view from side to side.
  • Vertical FOV: The extent of the view from top to bottom.
  • Diagonal FOV: The widest view across the frame diagonal.
• Influencing Factors:
  • Lens focal length.
  • Sensor size.
  • Camera placement and distance to the subject.

FOV in Trail Cameras: Narrow vs. Wide Angles

1. 60° Field of View (Narrow)

• Applications:
  • Ideal for focused monitoring, such as game trails or feeding areas.
  • Offers detailed, high-resolution images of subjects within the frame.
• Advantages:
  • Subjects appear larger and more detailed.
  • Suitable for areas with predictable movement patterns.
• Disadvantages:
  • Limited coverage area.
  • Requires precise placement for maximum effectiveness.

2. 100° Field of View (Wide)

• Applications:
  • Perfect for large, open areas like fields or clearings.
  • Useful in regions with unpredictable wildlife movement.
• Advantages:
  • Covers a broader area, reducing the number of cameras needed.
  • Increases the chances of detecting movement.
• Disadvantages:
  • Subjects appear smaller and less detailed.
  • Can make identifying distant animals more challenging.

Comparison Table: Narrow vs. Wide FOV

Technical Formula for FOV Calculation

Horizontal FOV can be mathematically derived using the following formula:
FOV = 2 × tan⁻¹ (Sensor Width / (2 × Focal Length))
Where:

• Sensor Width: The horizontal dimension of the camera sensor.
• Focal Length: The distance between the lens and the sensor.

Example:
For a sensor width of 12 mm and focal length of 24 mm:
FOV = 2 × tan⁻¹ (12 / (2 × 24)) ≈ 53°

Factors Influencing Field of View in Trail Cameras

1. Lens Focal Length

• Shorter focal lengths provide wider FOVs.
• Longer focal lengths result in narrower FOVs.

Examples:

• A 10mm lens offers a wide perspective, ideal for landscapes.
• A 300mm lens delivers a zoomed-in view for detailed wildlife monitoring.

2. Sensor Size

• Larger sensors enable broader FOVs.
• Smaller sensors restrict FOV, effectively cropping the scene.

Examples:

• Full-frame sensors deliver wider FOVs compared to crop sensors with the same lens.

3. Camera Placement

• Distance to the subject directly impacts the visible area.
• Closer placement narrows the FOV, while greater distance expands it.

FOV Applications in Trail Cameras

Wildlife Monitoring

• Wide FOV cameras (e.g., 100°) are ideal for monitoring large, unpredictable areas.
• Narrow FOV cameras (e.g., 60°) excel in capturing detailed images of specific trails or feeding zones.

Security Surveillance

• Wide FOV trail cameras can cover extensive perimeters.
• Narrow FOV models focus on entrances or specific assets for detailed security.

Examples of Field of View in Action

• Wildlife Observation:
  • A camera with a 100° FOV captures wide animal activity across a field.
  • A 60° FOV camera provides close-up images of a deer at a feeding station.
• Property Monitoring:
  • A 100° FOV camera secures a large backyard.
  • A 60° FOV camera focuses on a narrow driveway.

Conclusion

Field of View (FOV) is a vital feature of trail cameras, determining the scope and detail captured in each shot. Choosing the right FOV depends on your application needs—whether it’s capturing a broad landscape or focusing on a specific point. By understanding the nuances of FOV, users can optimize their trail camera setups for the best results.