System information

MX Cameras
3-6 Vicon MX Hardware System Reference
The sensor area used for capturing data through each MX camera
determines the maximum FOV available for a particular combination
of camera and lens. The area of the sensor is determined by its
horizontal width (h) and vertical height (v).
The capture frame rate for each MX camera can be configured in the
Vicon application software (for details, see the software
documentation). The configured frame rate will also affect the field
of view. Higher camera frame rates may make vertical windowing of
the sensor necessary such that the sensor area used for capture is
reduced in comparison to lower camera frame rates.
Another characteristic of the camera sensor is the image circle. This
is the sharp circular image that the camera lens casts onto the sensor,
as shown in Figure 3-4.
Figure 3-4: Image circle
The diameter of this image circle is the maximum area of usable
quality image that the lens can produce. Most lenses produce their
best image at the center of the lens, dropping off in performance
towards the outer extremes of the lens. This results in a gradual
darkening of the image towards the corners of the image, known as
vignetting. Theoretically, vignetting gets worse for wider angle lenses
and for wider open apertures, but the area at which vignetting starts
to occur depends on the lens.
Thus for optimum performance, the image circle projected should be
larger than the sensor area used by the camera. This ensures that the
entire sensor is utilized and eliminates the fall-off of light that occurs
towards the edge of the image circle. If the image circle of a lens is
too small for the sensor size, then the camera image around the edges
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