How does MultiSense handle feature detection at different ranges?

MultiSense sensors are stereo cameras, so they measure range by measuring the offset of features in the left and right camera.  The offset is smaller as features are further away, so error in the measurement increases with distance.  At large distances the offset cannot be measured, so no range is reported.  Optimal long-range performance would require the camera to be set to full resolution.  The MultiSense S21B with 8mm focal length lenses provides the best long-range stereo performance.  The minimum range of a camera is determined by how many pixels of offset the camera searches when trying to match features.  MultiSense cameras can be set to use 64, 128, or 256 pixels.  Using a higher number improves the minimum range for a camera, but also reduces the frame rate of the camera.  Our S7 provides the shortest minimum range of about 0.4 meters.