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Old 08-26-2013, 08:18 PM   #2
Chas Tennis
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Join Date: Feb 2011
Location: Baltimore, MD
Posts: 4,083
Default The time estimate is way too long. ?

That reference says
"How long is the time from buttcap position to the spring forward? At most, half a second."................

Here are some Nadal forehands. We can estimate the time it takes to go from the butt cap position to impact. 240 fps

The best way to do stop action single frame on Vimeo is to press the play pause button as fast as possible.

I count about 11 frames from the time that the butt cap is pointing at the ball until impact.
t = 11 fr /240 fr/sec
t = 0.045 second.

He says < 0.5 second.

I'd say that he is off by a factor of 10X. ?

[1/2 second recorded at 240 fps takes 4 seconds when played back at 30 fps, as in the Nadal video. ]

Last edited by Chas Tennis; 08-26-2013 at 09:17 PM.
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