Sunday, 26 June 2011

...We are men of groans and howls, Mystic men who eat boiled owls...

Last night I went ahead with a little experiment I'd seen recently in a YouTube video involving a thin metal tray, a sub-woofer, some cornflour and a bit of water. See video below;
 
Initially I found the video when I was inspired by a challenge I read about on dpreview, the challenge was already over but it made me look up what non-Newtonian fluids were and more pertinently, google the term "fun things to do with non-Newtonian fluids?"
(Next time I might google "stupid things to do with non-Newtonian fluids")
 
With this in mind I grabbed an old sub-woofer I had no intention of using again(though I could) and begun the experiment with a friend of mine called Gordon. A fellow dabbler in photography and other such things and always happy to assist in anything even remotely interpretable as chemistry.

The plan of action was very simple.
  1. Mix up some oobleck using cornstarch(we used cornflour) and water
    Most recipes I found say 1.5 parts corn-starch to 1 part water but we ended up adjusting the mixture to suit as we went. The ingredients are so simple you can play with it.
  2. Pour it into a tray
  3. Slap the tray on a sub-woofer/speaker 
  4. Ramp up the bass.
To avoid having to spend too much time poking the mixture and holding the tray down we simply used masking tape on the underside of the tray, strapping it directly to the speaker, which basically served the purpose necessary and meant we could concentrate on things like focus/aperture/shutterspeed/etc.
I decided to go for macro shots of the fluid as it bounced and formed it's tendrils and blobs as wide angles, whilst interesting and documentative don't have much impact or visual appeal I think. Due to the nature of the experiment however the fluid is constantly vibrating at a high speed which is again exaggerated by being zoomed in so close to the subject. What this means is it's necessary to shoot at a fairly high shutter speed.

I went for 1/1000th of a second in the end which seemed to suitably nullify any motion blur, this ofcourse required some carefully controlled flash. Too much light will easily over expose the already white liquid and/or plunge the shapes into heavy shadows while too little light can result in a total lack of definition in the fluid or of course under-exposure. Shooting at a high speed such as this though does have the advantage that you can hand-hold the shot quite easily. 

Anyway, what follows is my pick of the results.
That's a tea spoon by the way.
The above two shots had too little depth of field I think, thankfully what i focused on is fairly interesting to look at but it would've have been nicer to see the rest of the image clearer.

Really these photos exhibit a technique of what's called "high-key" photography. (Something I've previously been quite poor at in my opinion.)

Shooting a white subject on a white background is basically a challenge, any definition in the subject can only be obtained from well-considered lighting.
I think I've managed to achieve the effect I was after, if I was to do this again(which is likely) I would probably try to incorporate more colour, either using food dye or possibly some coloured filters on a couple of flashes.
Only question now is what to do next.