I've recently finished the Sensor Add-On for my Water-Drop-Project.
Now you can capture falling objects (mid-air, or in a basin filled with all kinds of fluids). If you're interested, visit:
English version: http://deloarts.com/en/arduino/water_drop_pro_sensor/
German version: https://deloarts.wordpress.com/2016/05/28/water-drop-pro-sensor-add-on/
If you don't know the Water Drop (Pro)-Project yet, feel free to visit:
English version: http://deloarts.com/de/arduino/water_drop_pro/
German version: https://deloarts.wordpress.com/2016/03/21/water-drop-pro/
Here's a little preview of one of my recent captures with clear water:
