Originally Posted by HSCoach
I expect we know the above is the case. For this discussion, if a ball contacts the strings in the exact center, then slides a couple of mm down during the dwell time, would you call that a center hit or below center hit? thanks.
I'm not sure who you are asking. I proposed a question only about the initial ball contact location, first contact, and a simple way to crudely observe it with videos.
Originally Posted by Chas Tennis
About 50 observations total should show how often the pros are hitting forehand drives in the top or bottom half of their racket faces. If a few good citizens could do 10-15 each we could get a preliminary answer.
If we had observed lower impact points then it would be interesting and need better measurements with higher speed cameras to see the entire ball contact time. Videos of this quality are probably not available for pros on the internet, Nadal's entire contact time at 5000 fps, etc.
I would call your example a center hit, a 5. The accuracy of these crude measurements is not expected to be "a couple of mm", it's probably not even +/- 2 cm. I divided the racket face width into 10 parts and estimated by eye which part it mostly hit in. My racket face is 27 cm across and 1/10th of that would be 2.7 cm. Saying it hit at 6 means that it is estimated to be closer to 6 than to 5 or 7.
This is just a crude measurement intended for a quick look to see if the balls were systematically hitting low, say, around 3 which was my best guess before looking more carefully at some videos.
This little myth may have cost me because I actually thought hitting in the bottom half might work better than hitting in the top half or centerline.
It still might for my
stroke if the racket tilt after impact has some affect. Next, I will be looking for how far off the center the hits are and how the racket tilts.