Camera calculators

The calculators enable to quickly find the connection between image sensor resolution, required Field of View (FOV) and the lens you need.

Definitions:
Nx x Ny – active camera pixels
HFOV x VFOV – Horizontal and Vertical Camera Field of View, full angle.
L – Object distance
A x B – viewable object field

FOV calculator 1

Given a Field of View of a camera in terms of length and width, at a given distance, calculate the corresponding full angles of the FOV in degrees.

FOV calculator

Horizontal FOV HFOV [deg]

Vertical FOV VFOV [deg]

FOV calculator 2

Calculate the horizontal and vertical FOV that will be obtained given an image sensor and lens. What determines the FOV viewable by an image sensor through a given lens, is the focal length of that lens. In practice, a lens is designed to support up to a maximal FOV angle. Some lenses have a built-in field stop, which sharply restricts the field beyond that certain angle from being viewable. Most lenses don’t, and the viewable field “fades out”, due to vignetting. The lens is specified to work within an image area called image circle.

Distortion

When calculating high FOV, it is important to remember in lenses providing ~>70deg, often distortion is present. Distortion applies geometrical transformations on the image, which may have important implication on computer vision application. Without knowledge of the design properties of the lens, it is not possible to determine these transformations and the actual FOV of the lens.

FOV calculator

Horizontal FOV [deg]

Vertical FOV [deg]

Focal length (efl) calculator

Considering a new camera, rarely a new lens is designed, in most cases existing lenses should be matched. Determining which lens is required for a camera, can be a complex task. A lens has dozens of parameters, the most important of which are efl (effective focal length) and f# (f-number, or f-stop). Focal length determines the first-order relation (magnification) between object and image.

Using this calculator find the efl for a given image sensor and for required horizontal or vertical FOV (the reference).

Focal length calculator

Image sensor resolution:
Required FOV

Results:

Required Focal length [mm]

Horizontal FOV [deg]

Vertical FOV [deg]

MTF Calculator

Upload a slant-edge image to obtain an MTF graph.

• Crop and upload only the edge, as shown in examples below.
• Minimal size: 150×150 pix.
• The angle of the edge should be between 3 and 10 degrees to vertical or horizontal.
• Must not be distorted, edge must be absolutely straight.
• Use good illumination, get reasonable contrast, no stains or artifacts, low noise.
• Appropriate image size: 50-100 kb.

Camera Resolution

Calculate the horizontal and vertical FOV that will be obtained given an image sensor and lens. What determines the FOV viewable by an image sensor through a given lens, is the focal length of that lens. In practice, a lens is designed to support up to a maximal FOV angle. Some lenses have a built-in field stop, which sharply restricts the field beyond that certain angle from being viewable. Most lenses don’t, and the FOV edges “fade out”.

Warning: in lenses providing >70deg, often distortion is present. Distortion applies geometrical transformations on the image, which may have important implication on computer vision application. Without knowledge of the design properties of the lens, it is not possible to determine these transformations and the actual FOV of the lens.