In the Blink of an Eye

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Objective
Using high-speed photography methods, I intend to
determine the force imparted on a golf ball when
hit with a driver, as seen below.
How?
To determine the velocity of the .046 kg golf ball, I will compile two pictures. The first will be the picture of the ball taken at a known time interval of .01 sec after being hit and the second a yard stick starting at the ball resting on the tee and facing the direction of the ball. The composite image will show the distance that the ball traveled in .01 sec. The time that the ball is in contact with the club will be figured by closeup shots taken breif instances after the collision to see when the ball breaks contact with the club. Completing these tasks will complete the data set needed to determine force including acceleration, velocity, displacement, and mass.

Exploding Pretzel
To give an idea of how short the exposure time is, this is a pretzel. Well, it was a pretzel. I shot it with a 1000 fps pellet gun. The sound from the gun set off the flash unit which has a duration of 1/30,000 sec. In that amount of time, the pellet travels only 1/4 inch. Because there is very little ambient light, the camera shutter is held open long enough to capture the event and only record the light incoming from the flash.
High Speed Photography
High-speed photography, or HSP, differs from normal photography in that HSP involves much shorter exposure times and the need for a method to take the picture at an exact instant.
Most decent single-lense reflex, or SLR, cameras have adjustable shutter speeds ranging from 1/2000 sec to however long the button is depressed on the "bulb" setting. Despite being the fastest setting on the camera, 1/2000 of a second is decievingly slow. In that amount of time a .68 paintball traveling at 300 fps would move almost 2 inches, creating a detail-void blur. In addition, the two blades of the shutter travel across the film plane at the same time with only a small gap between them. Each bit of film gets light exposure for 1/2000 sec but at different points in time. The picture evolves top to bottom catching the event in different stages.

The cure for the common mechanical shutter is to use a high-speed flash as the effective shutter speed. Commercially available units like the Vivitar 283 can be fooled into durations down to 1/30,000 sec. In that small amount of time, the golf ball does not travel a noticable distance. I assure you, however, that the club and balls in the photos are moving quite quickly. To take the picture, the shutter is set on the "bulb" setting; it is held open long enough to catch the light when the flash is triggered and closed. The film will only record the light from the flash assuming that the photographer did everything possible to cut down on ambient light.