I shoot a fair bit with long lenses for wildlife (birds). When tilting recently I noticed that at the end of a tilt down that the camera seemed to come back up a bit. While I realize that with extreme focal lengths this problem is amplified, I'm wondering if this is an issue with my fluid head or my technique. I was shooting with a C100II, a 500 f4L and 2X convertor, Manfrotto 504 HD on Gitzo cf sticks. Is this an issue I can practice or spend my way out of? I did have the rig balanced and the tilt wasn't extreme.