We all know that the LEM descended from the CSM to the moon's surface and then rose back again to dock with it. But there are some videos that show the CSM floating in the foreground with the moon's surface in the background. This was obviously shot from the LEM, which must have been at a higher altitude than the CSM. Hence my question - Did the LEM ever rise above the orbit of the CSM at any time?
By separating with the LM moving away from the moon, and the CSM towards it, the LM would be at a higher altitude than the CSM. As a consequence orbital mechanics cause the LM to start to fall behind the CSM, so when the descent engine was fired to slow the LM it wouldn't bump into the CSM.