Have you ever wondered how a picture like the splashing dice above was taken? Maybe you assumed the photographer had excellent timing (which is possible), but with this howto article from Make, you don’t have to rely on timing or luck, you can actually predict when the splashdown will happen and trigger the camera appropriately.
If you remember back to high school physics class, distance (d) traveled by a falling object is predicted by: d = 1/2gt^2 or you can just guess, as they do in the howto. The Make setup shown below starts a falling object with a solenoid, meaning that there will be a set time until the object hits the water. Whether you guess or calculate, things should be consistent once calibrated. Quite clever.
When I saw this splash photography rig, I thought that they were going to use a sensor to predict when the falling object was about to hit the water. If you could find an appropriate sensor for this, I think that would be a good way to do it. On the other hand, those kind of sensors can be expensive, and there would still need to be some guesswork, since you might have to offset it to not get in the way of the shot…
I’ll add this to the list of projects that I probably won’t get to. Anyone try something like this? Let me know in the comments!