Method

See diagram for a visual of the setup.

All the settings were constant throughout our project except for a few of the preliminary photographs used to find these settings.

The pictures were taken by dropping the ball into a cookie sheet filled with milk. One person hit the shutter on the camera and the other person (later to be the same person) dropped the ball when the camera beeped. To get the sequence of photographs found in the gallery, a time delay was used with the sound trigger. After every shot I turned the variable resistor a tiny bit with a screwdriver to increase the time between the ball hitting the milk and the flash going off. 

The flash unit was set by wiring a straight piece of wire (close to zero ohms of resistance) where the thyristor would normally go to get the shortest possible flash. The ends of the wire were placed in holes 2 and 5 (top right and bottom right) of the thyristor socket. One could use a variable resistor turned to zero or a paperclip in place of the wire I used. The shortest flash is desired so that the image being recorded on the film is from the shortest duration of time possible (the shorter the flash, the clearer the action will appear) 

I used a shutter speed of one second instead of the bulb setting to reduce thermal noise. If the shutter is open too long on a digital camera, even in the dark, the pictures will have small white spots on them. This thermal noise is caused by random electrical signals hitting the CCD chip (a digital camera's 'film').

The ball in the pictures is a Goooz ball. It gives very easily and will squish between your fingers if you put it in your fist and squeeze. When no pressure is applied the ball holds its round shape. A ball like this was desirable because it required less energy to get it to deform when dropped. 

For many of my pictures I used the highest resolution the camera would give me. This setting gave the clearest images but also made pictures with 1.5mb files sizes. I had to resize and compress all of them to nearly 1/60th of their original file size to get them to fit on the web. This has caused a great decrease in image quality.

I placed the microphone on a couple of paper towels before putting plastic over it. This seemed to help stop the double flash when the ball bounced back down on the dish. By bringing off the floor with the paper towels I reduced the sensitivity of the microphone because it was no longer getting vibrations through the floor.

After setting up taking pictures was a snap; all I had to do was open the shutter and drop the ball.

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High Speed Imaging at the North Carolina School of Science and Mathematics