CCTV Field of View & Image Detail Calculator

Lens

Enter the focal length of the camera lens.

Focal Length (mm)

Select the camera resolution and active sensor size.

Camera Resolution Sensor Size

Enter the mounting geometry used to assess whether the field of view intersects the ground.

Camera Height (m) Camera Tilt 0° points vertically down, 90° is horizontal and 180° points vertically upwards.

Calculated field of view and maximum image-detail distances.

Horizontal Resolution

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Horizontal Field of View

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Maximum Scrutinize Distance

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Maximum Overview Distance

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Maximum distance achieved at each BS EN 62676 image-detail level, with the corresponding previous DORI classification.

Level	Previous DORI Level	Pixels per Face	Pixels per Metre	Maximum Distance

Flat terrain.
Direct and unobstructed line of sight.
Correct camera focus.
Suitable and consistent scene lighting.
No material atmospheric degradation.
Optical magnification only, with no digital zoom.
Distances are calculated using horizontal pixel density and optical field of view.
The active vertical sensor dimension is estimated from the selected image aspect ratio.
Where camera tilt is entered, the maximum distance is capped if the far edge of the vertical field of view intersects the ground before the calculated pixel-density distance is achieved.