Paint Sculpture Tutorial

A Guest Post by Henning Huenteler from www.shutter-lag.com.

Paint sculptures are not only beautiful, they also offer a vast variety of different images that depend on many different factors. By experimenting with the main drivers, fantastic variations of different images can be achieved. In the following tutorial, I will introduce the equipment needed, the setup of all the gear and some first ideas for your own experiments.

General Setup

The general setup is pretty easy and a perfect first step into high-speed photography. All that you need is a camera with a short shutter lag (DSLR), (at least) one speedlite flashgun, a microphone to trigger the flashes, an old speaker and some balloons.

This is the setup I use for my pictures:

• Canon 60D Digital SLR
• Canon 580exII speedlite
• Canon 430exII speedlite
• Yongnuo 560 speedlite
• An old amp with a 2′ speaker attached (this is just an active PC speaker as you can buy in every Wal-Mart or electronics store).
• The Stopshot by Cognisys (see below for detailed introduction)
• Some rubber balloons

The Yongnuo flash doesn’t have any TTL functions, but has to be set up completely in manual mode. However, as I am going to set up and fire all flashes manually, this fits my need perfectly. The price is unbeatable! The units are around 350 RMB ($55) in China and should still be reasonable in Europe or the US.

The principle is really simple: The paint is applied on a rubber skin of a balloon stretched over the speaker. Once a sound is played over the speaker, the elastic rubber will start vibrating with the sonic waves and the paint will start ‘dancing’ on it. The picture has to be taken just at the beginning of the sound, let’s say 20 – 30 milliseconds after it starts, or the paint will mix and the single colors will not be clearly separated from each other.

Since even modern SLRs do have a certain shutter lag (for my Canon 60D, this shutter lag is around 85 ms with locked-up mirror), the right moment would already be gone when the camera is ready. Therefore, I cannot take the camera to actually take the picture, but I have to open the shutter and use the speedlites to actually ‘pick’ the right moment. The speedlites have a much faster reaction time and are perfectly suited to take the picture when you are working in a dark environment.

In order to freeze exactly the right moment, I set the camera into ‘bulb’ mode and use a cable release to open the shutter. To avoid a bright background in the image, I have my entire setup in a dark room with covered windows to avoid any light from spoiling the pictures. The only light visible in the picture comes therefore from the 3 flashguns I trigger just a few milliseconds after the paint starts dancing on the speaker.

Triggering

To trigger the flashes, you need some extra equipment. The Stopshot device I use will trigger my flashes automatically. If you just want to take pictures of paint sculptures, you would probably not need this, but I also use it for other high-speed photographies. Besides the Stopshot, there are several other devices including the Mumford Time Machine, the Arduino Board or the Hiviz Controller that will do the job. I guess the Time Machine and the Stopshot are the easiest one to use, as they come readily built with a nice manual. The Ardunio Board can be programmed completely individually and the Hiviz does not come as an assembled unit, but you have to build it by yourself. However, all of them should work well for this purpose.

If you are looking for a cheaper solution, it should also be possible to trigger the flashes with nothing more than a microphone, an amp and an ADC (but don’t quote me on that). I goggled the web for the specifications of the PC connector that is built into many speedlites, but there seems not to be a single standard. Different manufacturers seem to have different trigger voltages for the connection, but they all seem to be roughly around 5V. If you like to play around with some electronics, it should be possible to use a microphone, a little amp and an ADC to fire the flashes via the PC connector. If your flashgun does not have a PC connector, you can also take a hotshoe with a PC plug sold for a couple of bucks on the internet. To fire more than one flash, either use hotshoes with two connectors to daisy chain the speedlites or connect a Y-cable to your amp.

Flash setup

For the location of the flashes I usually choose 5 and 7 on a clock face, where the camera is on the 6 and the speaker on the 12. As I need to have a real short distance between the camera and the speaker and I need the paint to be illuminated from two sides, I need to dial down the power output of the flashes to reduce the light to a suitable amount.

Another reason to dial down the output power is the flash duration. The paint is moving really fast and a flash fired at full power would be way to long to freeze the action. There is a nice overview on the flash durations of all the flashes I use on http://speedlights.net/. With 1/1 power, the Canon 580exII has a flash duration of 1/285s, which is way too long. With a power of 1/128, this goes down below the minimum duration measurable with the meter they used (<1/8000s). This is just suitable for my purpose, so I usually fire all three flashes with either 1/64 or 1/128 power.

Camera Setup

As mentioned before, I set the camera into bulb mode and open the shutter with a cable release. Although I work in a dark room, a try to keep the exposure time as short as possible, so I open the shutter, start the sound and as soon as the speedlites fire, I release the button again. The entire process of picture taking does not exceed 1 second.

To further improve the image, I usually shoot with ISO 100 or 200 maximum and close the aperture down to 13 or 16. By that, the image gets less noisy and I end up with a high depth of field. Closing the aperture even more would reduce the image quality, so you have to find a balance between sharpness and depth of field.

Paint

For the paint, I usually use gouache. Gouache is more viscous than watercolor and has a stronger, shinier color. I usually mix it with a little water, just to get just the viscosity I need. Here, you have to play around a little bit and see what gives the results you like best. Depending on the viscosity, the paint will look and behave differently. You can achieve everything between thick honey-like syrup to a splashy watery liquid.

To apply the paint on the rubber, I usually use a straw or a spoon, depending on the viscosity. I just use 1 or two drops per color. This is enough to throw the paint up in the air when the balloon is vibrating.

Sound

The sound that is used to make the balloon vibrating on the speaker is essential for the images. There are different factors that influence the behavior of the paint:

• The volume or intensity of the vibration obviously has an impact on the intensity of the paints’ reaction to it. A loud sound will make the paint explode into the entirety of the room you are working in, while a very low volume will have no impact on the drops at all. You have to experiment a little bit to find the right amount to fill your frame but not end up sticking at the ceiling.
• The frequency will influence both, the intensity of the vibration and the shape of the paint sculpture. While a very low frequency will only result in a movement of the rubber skin with the paint on it, a high frequency will be too fast for the sluggish paint to jump up and start dancing. For my pictures, frequencies about 80 – 200 Hz where just right. Trying out different frequencies will give you a feeling for the effects you can achieve. The difficult thing is actually to decide which one you like.
• The timbre finally can shape your vibrations and create thousands of different sculptures. Go and try it out!

  I usually generate the sound on an attached notebook, but you can probably use whatever source you want. A keyboard or even your electrical bass guitar would probably do. On my Mac I use the open-source software Audacity, which is very versatile and gives me the tools to experiment with all the parameters.

Background

For my pictures, I usually use a black background. This is much easier than using a white one, especially for the beginning. By using snoots in front of my flashes and setting them in an angle to the direction of picture taking, I prevent any light from spilling on the background. Especially after some pictures, the background will be spilled with colorful drops, so you will see any reflection in your pictures if you are not careful with the direction of lighting.

Using a white background is much more difficult. I use at least one flash to directly light the background, but even then I usually have to improve it a little bit during the post-production. Another thing that makes white backgrounds difficult is the balloon. Even a white balloon will never be 100% bright, so it will be always visible if on the picture. One way to prevent having a grey balloon in the foreground is to exclude it from the photo frame. By doing so, the picture will only consist of the flying paint in front of a bight white background.

Post-production

The post-production is fairly easy and there is not much to do if the shot is prepared well. I sometimes stamp out some drops of paint flying around and disturbing the entire composition or some areas where the background is not 100% black or white. Apart from that, I apply only some exposure correction or level adjustment and some sharpening. Voila, that’s it.

Feedback

I tried to be as comprehensive as possible in this tutorial. If there should be any questions left, just ask in the comment section below and I’ll try to answer them all. The really important part about this is having fun during the shooting. All these setups can take a while and it can get quite frustrating to always clean up the balloon and prepare the next shot just for a process of picture taking that lasts well below one second. Especially, when I am experimenting with the trigger or the sound settings, it often happens that I set up everything correctly and just forgot one thing or the trigger doesn’t fire, so I end up flecked in paint and without a usable picture. Just remember: it’s all about the fun. And one more thing: put on some old clothes and cover all sensitive carpets or computers around.

Henning Huenteler is an enthusiastic amateur photographer from Germany, currently living and working in Beijing, China. He is mainly doing landscape and highspeed photography and is the author of www.shutter-lag.com.