Dropping colored milk into water and photographing the effects is nothing new – these experiments have existed for decades and can yield some very interesting abstract images. The technique can be brought into the “mad scientist” realm by switching gears slightly – using UV flashlights and fluorescing ink, we can make it glow!
The ingredients here are simple:
There are a few challenges to consider – one of which is focus. The best solution is to pre-focus on something in the water (I use kebab skewers) and mark on the sides of the tank where this is. There will be some deviation from this point when you drop the ink into the water, but shooting with a wider field and F/11 should give you more than enough depth. The camera should also be angled slightly up, so that you can get a bit of the surface of the water in the frame which will offer up reflections, adding an extra bit of dimension to the images. I find that rotating the images 180 degrees offers up a fun twist on these fluidic sculptures.
Turn off the room lights, turn on your UV flashlights, and begin experimenting! Your first tank of water will likely be used just to dial in your exposure. This will depend on how many UV lights you are using (two lights, one on each side, is a great place to start) and how fluorescent your liquids are. I found that with four lights, F/13, 1/200sec and ISO 1000 were working well, but these images survive noise reduction very well so don’t be afraid to push further.
The shapes created when you drop the ink into the water are caused by the Rayleigh–Taylor instability. The two fluids have different densities which cause beautiful interactions, and the same physics is responsible for the shape of mushroom clouds and supernovae. Thankfully, this experiment is far less destructive.
The artistry comes from how you make the shapes interact, how carefully you time the drops of ink, and even how you prepare the water – adding a current from heating part of the tank, for example, will affect the flow of the liquids. There is a strong element of randomness to this, and you’ll never get the same results twice.
So, now you’re set up for shooting UV fluorescence images! What else can you shoot? Minerals, flowers, and more! Check out this video recorded with Chris Niccolls of DPReview TV on UV photography, including a tutorial on “Liquid Flow” as seen in this article:
For more inventive approaches to macro photography, check out Don’s upcoming book, currently available to pre-order.
About the author: Don Komarechka is a nature and macro photographer who specializes in snowflakes. He has published a book, Sky Crystals, which details the wonderful science of snow in addition to an exhaustive photographic tutorial from equipment through settings, techniques and post processing. His work on the subject has been featured in documentary films from CBC, BBC, and National Geographic as well as on limited edition Canadian currency. Komarechka hosts the podcast Photo Geek Weekly. You can also find more of his work on Facebook and Flickr.