When the motion data is captured, it is sampled at a rate relative to the current frame rate, which defaults to 30 frames per second. Increasing the frame rate increases the sample rate. The two radio buttons in this section allow you to choose 1 or 2 samples per frame. This is a short cut to let you sample at a field rate. If you’re rendering to fields, you don’t necessarily need to capture at 60 frames per second. Controllers will interpolate between the samples.
When Reduce Keys is active, the keys generated by the motion capture are automatically reduced, using the same algorithm found in the Reduce Keys function in the Track View. The Threshold spinner is also the same as the Threshold function in Track View Reduce Keys. (Spinner Value: float, 0 to 999,999)
Note: When Reduce Keys is active, there is additional calculation time after each completed recording.