(03-05-2018, 04:33 AM)JackCity Wrote: They use a pressure pad and several different lasers to determine the start time and the finish. It's highly accurate.  

The time you see on the screen is the unofficial time. Basically a highly accurate estimation.  They then get their times and cross reference it against multiple systems to see.

I don't want to belabor the point, but the video is simply a recording of the run. The digital video rate is 30 frames a second. For every thirty frames of video you count - frame by frame - one second of time has transpired.

Go to You Tube, find the NFL video, and cue it up by pausing it, then advancing frame by frame to the start of Griffin's 40 yard dash. You move the video using the comma (,) key to advance backwards or the period (.) key to advance forward one frame at a time. 

One frame equals one thirtieth of one second. If you tap the period (.) key once you have advanced the video one-thirtieth of one second. Tap the period (.) key thirty times and you have advanced the video one second.

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