One reason for turning off

One reason for turning off the stabilizerwhen on a tripod is that if you try to pan the camera, it will first interpret this movement as shake and will try to correct for it. This causes an initial delay in the pan followed by a catch-up jump in the video. So, with the stabilizer on while doing a pan from a tripod will actually cause a jerk in the video! The stabilizer is designed to make up for the lack of a tripod.