Video as radar gun

[Dave D]

Just thought I'd throw this out as another way of measuring a pitcher's speed accurately without using a radar gun (especially as most everybody's gun seems to calibrated differently).

This method is not perfect, in that pitches slow down as they cross the plate, and this measures the average speed of the pitch from hand to glove, not the speed at one point in space. It seems pretty accurate, though. What's really cool is taking video from a dad who swears he gunned his 12 yo at 59 mph and showing him with the chart that she's really throwing 49. Hard for them to argue at that point.

You could also use the chart below with a stopwatch, but that kind of timing is REALLY hard to do accurately.

Most pitchers use video to track progress and document motion, and most of those people (dads like me) have some kind of editing program on a computer. With those tools, the process is simple:

1. Make sure the pitcher is at a set distance.(40 or 43 ft)
2. Set editing program to frame by frame.
3. Count frames from release to catcher's glove contact (be sure to add distance if pitching distance is to the back of the plate and catcher is behind the plate)
4. Standard video runs at 30 frames/sec (actually 29.97, but, whatever)
5. Convert frames to seconds (15 frames =.5 sec.)
6. Check the chart

Pitch Miles Per Hour
time(sec) 46 feet 43 feet 40 feet 37 feet 34 feet
0.60 51.98 48.67 45.45 42.03 38.63
0.59 52.86 49.49 46.22 42.75 39.29
0.58 53.78 50.34 47.02 43.48 39.97
0.57 54.72 51.23 47.84 44.25 40.67
0.56 55.70 52.14 48.70 45.04 41.39
0.55 56.71 53.09 49.58 45.85 42.15
0.54 57.76 54.07 50.50 46.70 42.93
0.53 58.85 55.09 51.45 47.58 43.74
0.52 59.98 56.15 52.44 48.50 44.58
0.51 61.16 57.25 53.47 49.45 45.45
0.50 62.38 58.40 54.54 50.44 46.36
0.49 63.65 59.59 55.65 51.47 47.31
0.48 64.98 60.83 56.81 52.54 48.29
0.47 66.36 62.13 58.02 53.66 49.32
0.46 67.80 63.48 59.28 54.83 50.39
0.45 69.31 64.89 60.60 56.04 51.51
0.44 70.89 66.36 61.98 57.32 52.68
0.43 72.53 67.91 63.42 58.65 53.91
0.42 74.26 69.52 64.93 60.05 55.19
0.41 76.07 71.22 66.51 61.51 56.54
0.40 77.98 73.00 68.18 63.05 57.95
0.39 79.97 74.87 69.92 64.67 59.44
0.38 82.08 76.84 71.76 66.37 61.00

 

[Dave D]

Sorry the number chart got mashed up together. It was spaced out correctly on the preview window. If anyone wants the Excel spreadsheet file, I'll be happy to send it to you.

 

[sluggers]

You could attach it as a text document if you want. Go to "advanced editing" and then click "manage attachments".

Ray

 

[coachdan]

Dave I would like the spreedsheet, could you email it to me
coachdan12u@hotmail.com

thanks Dan

 

[Poseidon]

Hi Dave,

I tried this method a couple of years ago and discarded it because of the relatively large error in measurements in addition to the fact that you are measuring average speed instead of nearly instantaneous hand exit speed.

Because you are using a video analysis you are getting a measurement resolution of 0.033 second. This temporal resolution provides a rather large error in trying to discriminate between speeds. If we take 2 rows of your spreadsheet for a 37 feet pitching distance:

J
Pitch Miles Per Hour
time(sec) 37 feet
0.47 53.66
0.44 57.32

Hence, this method will provide a minimal error of +/-4 mph. Furthermore, the measurement error will be compounded by the fact that unless you are using a short shutter duration you will have difficulties in determining when the ball hits the catcher's glove (most probably another 1 frame of error).

Hope that helps,
Michel

 

[Renntiger]

My Casio EX-F1 can produce VGA quality videos at 300 fps (essentially a 10x slow-mo), so I am able to make fairly accurate speed measurements based on those videos. Counting more than a hundred frames for each pitch would be too much of a chore, but using a stop watch while playing the video and shifting the decimal point to the left would produce a read out that's accurate to within 0.001 seconds, theoretically.

My experience has been that there is little difference in outcome between this approach and the use of a cheapo Bushnell radar. The latter is certainly a lot more affordable than an EX-F1, and provides instant gratification. The one real advantage enjoyed by the video approach that I can think of, aside from the obvious benefit of providing a platform for motion analysis, is that you can use it to scout opposing pitchers from a great distance during tournaments. But then again, knowing exactly how fast the opposing pitcher is throwing is not the most actionable part of such analysis.

GT