Vic was a pioneer. He started with actual movie film and did several famous studies--the one of Tanner's serve and also of Ken Rosewall's backhand. He told me it cost him $1000 everytime Ken missed one. The problem with film other than the expense is the difficulty of set up, the constant reloading of the magazines, etc. I know because that is how we shot McEnroe/Lendl--35mm film on a soundstage. There was a guy even before Vic, Stanley Plagenhoff who has been more or less forgotten. He did filming of Laver and many other I was told during an actual pro event. Again this was movie film. A few years ago I contacted his widow hoping to find out more about what had happened to his work. I also called his son. The story apparently was that after Stan died the family was cleaning out the house and, you guessed it, threw it away... tragic... I used to tape pro matches and then make frame by frame video prints of the stroke sequences in replays to try to see what was actually happening. Everything changed with the advent of high speed video, but more importantly, storage capacity. Remember the original Mac cams at the Open pre shot spot that showed replays of the line calls? Those only stored a few seconds. But in 1997 the same company brought out a system that could record at 250 frames/sec to tape. Working with USA Network, the USTA and some collaborating researchers from the aerospace industry, we were able to film there with that system in 1997. That was what set the whole data collection revolution in motion. The problem of course is that the eye sees only at about 20 frames a second. Any event that is shorter in duration--like the contact with the ball--is a blur. What high speed video did was allow us to see inside the invisible world for the first time and most importantly in live match play. So far I have yet to work with a coach who didn't learn something or revise a previous view based on the study of this footage. Of course now Brian Gordon's work is taking this even to the next level with quantification. The exciting thing though is that our understanding is progressing through the creation and discussion of these data bases.