Capturing fast events that are otherwise missed by the naked eye is fascinating. Things that we see everyday and believe to know how they happen are sometimes much more complex. With beautiful, otherwise invisible, in-between states.
One such example is the life of water drop as it hits a surface. As the drop hits the surface a corona is formed around the center. This can be done with both a hard surface as well as with a liquid surface to land on. As the event we want to capture is very quick it is important to either have very good lightning and fast shutter speed or use a flash to control the exposure time. See previous posts on High Speed Photography.
Depending on the speed of the drop, the surface tension of the fluid it lands in and several other parameters there may also be a re-bounce. By altering the mixture of the the liquid that is dropped and the liquid that it lands in it is possible to achieve very different re-bounces.
Food coloring can be used to give both the drop and/or the the liquid to land in different appearances. To control the surface tension I use dishwasher rinse aid. Corn starch can also be used to increase the surface tension (rinse aid reduces the surface tension). Another variable to use is different colored screen to get alternate colors.
Then with varying drop size and timing it becomes possible to shape the column formation to achieve different shapes and expressions.