Sadly, MPH isn't the base consideration in taking pictures/video of such things. You are right that shutter speed is important but let me just write this and I will NOT edit this over and over as if I'm writing for any magazine. This is a conversation and nothing more.
The first issue is how much movement across your frame the "things" move while the shutter is open. This is the blur issue.
The next issue is how many frames per second you can run at to capture high speed events. This one, as far as your run of the mill camcorders you see at the stores is moot since they all shoot at NTSC/PAL or near some standard 30 Frames Per Second or FPS.
The blur issue is simply. The NEAT thing about this is that your video is likely to be in sunlight which is terrific since a well lit scene drives the shutter speed down. At the light decreases, shutter speed goes up. And the other effect may be the iris will open. I'll leave you to think over the interplay of shutter speed and iris openings.
The upshot of all this is that you won't always get a lot of frames from the beginning to the end of the golf swing, but you will have enough to see if your form is ok.
Have a good one,
Bob
Hi I have just begun looking for a digital camcorder. I am an avid golfer and always looking to improve my game and I would like to know it the shutter speeds of most digital camcorders are fast enough to create a sharp picture in slow motion playback of someone swinging a golf club (say at around 115 miles/hour)? I really dont even know how fast of a shutter speed that would require. Also any suggestions on which camcorder I should get do this?

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