I guess anyone trying high speed pics has a go at the splash. So todays mission was to see if it could be done with a variation of the contact trigger.
For the first attempt I thought to use the liquid as part of the circuit. Despite making contact through a meter it failed to trigger the flash. Electrical boffins will know why that is.
A bit of a think and I decided on a floating trigger using a bit of foil. The idea being that anything dropped into the liquid would create a wave. The foil would ride the crest of the wave and so make contact with the fixed terminal. This works fine everytime so long as the top of the foil is dry along with the fixed contact. Any wetness here and it will fail to trigger the flash.
Water was put in the bowl up to 10mm from the top. The trigger was then positioned before adding the remaining. The foil floats well enough so it is quite easy to raise the water level and float the foil up to give a gap of around 1mm. This spacing is dependant on how large an object you intend to drop since it must be less that the wave that will be generated. 1mm is fine for an ice cube but for something smaller that and gap would need to be smaller and or the trigger placed closer to the impact point.
Provided the contacts are dry and a suitable gap is set this is guaranteed to work every time. My only failures were through forgeting to connect the flash
, not topping up the water after that failure
, and two more before I realised the significance of wet contacts. So 6 frames were taken to get the gallery pic and the full frame posted here.
Attatched is a pic of the floating trigger, a full frame showng the contacts, and a behind the scenes shot.
Don
PS : As the wave rebounds from the container side it will trigger the flash again as the foil rides the wave, so an assistant to cover the lens with black card directly the first flash burst is over is advisable if you are using a long exposure like me at 2 secs. 2 secs chosen for trigger the camera and drop the ice cube.