Set-up

    This is our final set-up...
 

*view from the camera.

Pertinent distances:

Flash to trigger: 0.4 meters

Camera to trigger: 1 meter

Background to trigger: 0.4 meters                                     

1. The apparatus was set up according to the diagram above. We taped a copper plate contact trigger to the table and connected it to the either the delay unit/flash or just to the flash unit. The flash unit was placed in front, and slightly to the left, of the copper plate so that the illuminated portions of the balls were visible to the camera. The camera was directly in front of where the collisions were to occur. Usually, Anne would stand on the table and drop the two balls in succession about 1 meter above the plate. We coordinated the ball drop and the opening of the camera shutter by simple counting coordination (one... two... open... drop). 

2. We set the camera and flash features according to the table below.

NOTE: The time delay was not fixed, sometimes we used no delay, sometimes an increase. These changes are recorded for individual pictures.

3. With this set-up, we took pictures of colliding balls with combinations of two racquetballs, two tennis balls, or one tennis and one racquetball.  We found that it is easiest to capture the collision of a racquetball beneath a tennis ball.

* This is the final setup. See the photojournal for additional information on previous setups and steps to reach this final stage.