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This is a special parameter that only applies if your panorama is not a full 360 degree panorama. In this case, the panorama motor has to guess the center of the first and the last image so the final result will have the desired angle. To do so, it needs to know the horizontal angle of the field of view the camera is set to.
North deviation
If this value is set to 0 (zero), the natural home position of the camera will be treated as facing north when calculating the parking position. In case the camera is not mounted facing north, this value must be set to the angle relative to north in degrees.
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