High-Speed Smash: Glass • Travis Hale (Photography and Science)

High speed photography is an area of fascination for me, there is simply so much fun that can be had with smashing stuff at high-speed, be it balloons or glass bottles. There are a few tricks to the trade through, so I thought i would share some of these with you. In reality the camera shutter is far to slow for most high-speed photography maxing out at 1/4000 or 1/8000 depending on the camera. To get around this a number of clever people have developed tools which are designed to join the camera, and the flash to maximize the ‘apparent' shutter speed.

In my case, i used a device called the PhotoTrigger which is a small micro-controller, it connects between the camera and flash and has a number of sensors which can be attached to the device (including sound). By taking a picture in almost complete darkness, with the shutter open (in bulb mode) the flash essentially acts as the shutter, and can ‘freeze' motion. The trick with the flash is that the lower the power, the faster the flash so you want to have this as low as possible.

The process is as follows;

Attach the glass to a piece of fishing wire and the ceiling / roof beam
Position the camera to capture the image (but not get broken)
Position the camera flash in an appropriate area, at its lowest setting
Position the high-speed trigger, with sound near the camera.
Manually focus the lens on the glass, I would suggest a lower aperture but still try to maintain some DOF (say f5-f8)
Set the camera into bulb mode (15 – 30 seconds)

Once you are all set, it is time to set up the high-speed trigger, set it to sound mode and set your various thresholds (e.g. minimium sound level to trigger), since all triggers are different it is worth consulting your specific user manual. Once this is set, and connected to the flash before you turn off the lights do a quick test (clap your hands) which should trigger the camera flash.

Now that you have confirmed it is working, turn off the lights and do another test, place the camera in bulb mode and trigger the shutter. Next clap your hands to fire the flash and wait until the exposure has finished, then check the image to see if you need to adjust the aperture (e.g. f4), or change the flash brightness.

Given all is working well, now for the grand finale. Turn off the lights and trigger the shutter on bulb mode, wearing appropriate PPE next smash the glass with the hammer, the sound should trigger the flash which will ‘capture' the image similar to the below. Note at the end you may need to do some Photoshop to remove the fishing wire.