How to Build an LED Light and Make an Orb
This article will tell you all about the what, where and when of orbs. Let’s start by defining them.
What’s an orb?
Well it’s both a cool, and fun, method of light painting that anyone can do. Basically you make a circuit with some LEDs (light emitting diodes), a battery, some wire, and a switch. You weight the LEDs, and then spin these in a circle as you move around a fixed point. Shot outside in the evening using a long exposure, this spinning creates a really cool looking sphere. By using different LEDs, you can make these spheres (called orbs) in different colors. There’s a small bit of tech involved in building them, but it’s not super hard. It’s also a project you can very definitely do with your preteen or early teen child.
The minimum you need to make an orb is:
- An LED (or a few LEDs to make it brighter)
- Battery Clip
- Push button to make a switch
- A weight: literally anything to make the LED at the end of the wire heavy, so it spins easily
- Resistor(s): The value depends on the type and number of LEDs you use
- Soldering iron, solder, wire cutters, and PVC tape
Building your LED light
Note from the Editor: Please take extreme safety precautions if you attempt this yourself. If you are not familiar with electronics get help from a friend or someone who is an expert.
Now for the tech bit. Attaching an LED to a battery can fry the LED. So to protect it, you need to use a resistor. You may need more than one if you use an array of LEDs. Use this LED Array Wizard, and finding the values is painless. You can enter in information about the LEDs into the wizard and get both the circuit, and the resistor values.
I bought the parts for this orb locally from a Maplin store (UK based), but you can get them from any electronics components store . Make sure to find the LED Forward Voltage (often 2-3.3 volts) and the current (often 20-30mA) for the LED Array. For this project I got four orange super-bright LEDs, with a forward voltage of 2v and current of 30mA. The wizard suggested I wire them in series and use a 39ohm resistor. (As it turned out, I had two red and two orange LEDs).
Soldering this together takes a little skill. The trick is to tin the wires, LED Legs, etc., before bringing them together to solder the connection. Pay attention to the connections.
The red wire from the battery clip should go to the switch, and the black wire should go (via the other wire) to the negative legs of the LED Array (or resistor in this case). From the other side of the switch, the wire should go the the positive side of the LED Array.
For the array, make sure to connect the LEDs correctly, as they only work in one direction. Generally one leg is longer than the other, indicating the positive terminal. Follow the wizard circuit to be safe. The resistor can be wired in any direction. Wire the array, then connect the wires from the switch, and test the circuit before committing to the final solder.
I’ve used an old adaptor nut as a weight. Even if your weight might fit over the LEDs, put it on the cable before the final solder, just in case. Once you’ve done the soldering, test again, and then use insulation tape (PVC tape) to wrap around each LED leg and the resistors, making sure none of them can touch any other. A short here could prevent the orb from working.
Use the tape to secure your weight. Give it a test spin. You should be able to hold the battery and switch in one hand, and spin with the other. Practice getting the spin right, before pressing the switch.
Spinning technique to make the orb
You’re nearly ready for the real deal, your first orb shot! But first, you need to master a key technique – centering the orb. The first thought is to spin the orb around yourself, but this won’t actually make an orb, it just makes a mess. I mean it looks okay, but it’s not an orb. To get an orb, the center of the spin must be static. Essentially you need to shuffle around your spinning hand to make it work. A great tip is to put something on the ground – a coin helps because you can see the light hit it – and spin above it.
It takes practice to get perfect, and plenty of my orbs are not perfect, but they still look okay. They are loads of fun either way! Some people shuffle forwards, I tend to shuffle backwards. See which one suits you best.
Next you need to know how to set the camera. Here’s the exact setting to use: er… there is none. It depends on what you want in the photo. You need the exposure to capture the LEDs, and your surrounding area, at night or somewhere dark usually. This means a minimum of 30 seconds, but generally longer. So, you need to use Bulb mode on your camera, along with a remote cable. It may be obvious, but you’ll need a tripod to hold the camera steady during the exposure.
Bulb mode means the camera will record the image, as long as the shutter button is held down. If you use a remote cable with a button lock, you can set the remote, walk off, do your orb, come back to the camera, and then release the lock to end the exposure. As long as the button is held, the camera will continue exposing.
Take an initial test shot of your location with settings of about 30 seconds at f/8, ISO 100 (see image above). You’re checking that the location will expose correctly first. Change the settings to get the exposure you need. If you’re on your own, use the 10 second timer on the camera to allow yourself enough time to get to your start position. Swing the orb, and once it’s moving, press the switch to light it up. Spin around a fixed point as recommended. That’s it. Go check your camera at the end and then refine your exposure.
Anywhere that the orb looks out of place makes for a great shot. Also wet ground or still water is great, as you get reflections of the orb as well.
Once you’ve gotten the bug, you’ll realize that the battery area is a bit flimsy and needs something more solid. For my own orbs, I put the battery and switch into a metal box with a 1/4 inch jack socket. I added a matching jack plug to the cable, replacing the battery and switch. That way I can use one box with a number of different coloured orbs. That’s a project for another day. Have fun making your orbs!
Have you ever tried this technique before? Or are you itching to try this? If you do – please share your images, and any questions, in the comments below.