I will show you how I do it. I’m sure that there are different methods you can follow but the way as I describe the process on this page, works fine for me. I want to warn you beforehand; it is going to make a mess so make sure that you protect your camera, flashes and Pluto from paint flying around by covering them in a transparent plastic freezer bag.
Making dancing paint photos requires a lot of preparation, such as masking the workspace in plastic to prevent that everything gets covered in paint. You will have to dilute the paint for the right viscosity. Then find the right volume of the amplifier and the right frequency in the tone generator app. You will also have to clean up in between and afterwards. And clean up again,... You have been warned, it causes a lot of rubbish.
I would start with making a speaker box out of MDF. Mount a speaker of about 15cm in it. Saw the pipe to a height of about 3cm and glue it over the speaker. Cut a circle out of the balloon and stretch it over the pipe. Secure it with the pipe clamp. Cut the excess of the balloon away.
Connect the speaker to the amplifier. To get a tone that make the speaker vibrate with the right frequency, I use a tone generator app that you can download from the Google Play Store or from the Apple App Store. I have it installed on my tablet so I can use the tablet for the tone generator and my phone to control Pluto.
I use three off-camera speedlights that are controlled by Pluto. Two of them are pointed at the speaker from left and right. The third one is used to light the background. For me it worked best with the speedlight positioned between the speaker and the sheet of milky plexiglass, pointing upwards. I also tried to light it from the back but I then got a bright spot on the background. Positioning the speedlight differently can avoid this. As a background I usually use a sheet of milky plexiglass (Perspex) This is easy to clean.
I usually have the camera on f-16 or f-18, ISO 400 to 600 and the shutter speed set on 1 second. I have my speedlights set on 1/64. You will have to do some experiments with this to see what gets you the best result.
Mix the acrylic paint with water to get the right viscosity. Thin paint will result in small drops that go all over the place. A bit thicker paint will make longer, solid drips. I use a spoon to put drops of paint (15-20mm diameter) on the rubber membrane. Again, you will have to do some experiments with this to see what gets you the best result.
With the camera on manual focus, place a matchbox or something like that on the middle of the balloon covered speaker. Make sure to position it where you will place the drops of paint. Manually focus on the matchbox.
Now do a final check;
Is the speaker vibrating when you use the tone generator? (By the way, I use 30 to 50 Hrz usually.)
Is the volume not to loud? If it is, you will end up with paint on the ceiling or other places you don’t want it to go.
Do a few dry-runs. Are the speedlights working? It is frustrating when they don’t. You will have to clean up when you didn’t even get a single shot.
Now we'll go and make a mess!
Activate Pluto in sound mode.
Put two or three (or four) small spoons of paint aligned over the speaker membrane. Experiment with different colours and quantity of paint. You can also use metallic paints and see what that does.
Turn off the lights in the room. Tap the table top to have Pluto open the shutter and straight away, activate the tone generator. The speedlights will flash. Make sure to turn of the sound a.s.a.p. to prevent the paint from flying all over the place.
Check the results. You can adjust the volume, frequency, flash delay and the paint colour or drop size.
Clean the rubber membrane and background, and start all over again.
On the above photos, I did not have the plastic bags on the speed lights and Pluto. Don’t forget to put them on! I’ve cut out a hole in the sheet of a bin liner to stick the lens through and let Pluto control the camera shutter via IR.
You can clean up your shots and adjust colours etc. in Photoshop or Lightroom.
Please, after each shot, check that no paint landed on your lens, camera or other equipment. Clean it right away. It is not worth it to ruin your equipment to get a shot!