Article by Peter Bargh - updated Feb 2012.
Remember as a kid playing with a Spirograph? For those who don't, it was a plastic geometric drawing kit comprising various shapes with small holes where a pen tip could go. You placed the plastic shape over a piece of paper, put a pen in one of the many holes and then used the pen to push and rotate the shape around another stationary shape. This produced random circular patterns, and introducing new shapes added new levels of complexity to the patterns. Using different coloured pens made the shape even more interesting.
The kids of today have moved on from Spirograph and now humour themselves with far more advanced stuff on Wii or XBox consoles, but us photographers can go back to our childhood and produce similar Spirograph pictures using our cameras, with a torch as the drawing tool.
- Camera with a long exposure mode
- Wide angle lens
- Small torch
- Sticky tape
How it works
The idea is simple, you suspend a torch from a ceiling or high fixture using string and set it swinging in a circular motion.
The camera, positioned on the floor, records the light path of the torch. Take the shot in a darkened room. Night time is best to save having to block light out.
Set your torch up
The first step is to sort out the torch you need a narrow light point and most torches are design to give a wider spread. Maglite make a really good torch that has a focusing beam to narrow the beam, but I wanted to show you how it's done on a budget, so I used a cheap £1 torch from Poundland.
The beam is quite uneven on one of these torches and spreads far too wide so you need to narrow the light into a small point. Do this by cutting a piece of black card and making a cone shape over the lamp. I used the front cover page of a high quality magazine which had a black advert on the inside.
Tape this in place so the hole at the base of the cone is the furthest point from the lamp - almost like putting a wizard's hat over the lamp. Make sure the hole is in the centre so the light is even when it's swinging.
Tie string to the torch
Now tie some string onto the bottom of the torch making sure when it hangs the string line is going up from the centre of the base of the torch.
Then attach the string to the ceiling. I didn't want to put a pin in the ceiling so I tied the string around a spotlight. If you follow my approach just make sure, if you use a light fitting, that you're not using that light in between taking the photos or you could cause a fire.
Set the camera up
Once the torch is in place get the camera ready. It needs to be placed on its back with the lens facing up towards the torch. When the torch is hanging still the centre of the lens should be directly underneath. To make sure it's in the right place switch the torch on and position the lens under the beam.
The camera needs to be set to a long exposure. Most cameras have an auto setting of 30seconds but it's better if you can set this manually or even better if the camera has a B-setting (Bulb mode). With bulb mode the shutter stays open while ever the release is pressed down. Most cameras have either a cable-release option or a wireless remote and in both cases you can usually set the release to lock so the shutter stays open without you having to hold it open.
The ISO can be left on ISO100 and the aperture will need to be experimented with to see how bright the beam is. With digital cameras you can shoot, preview on the LCD, adjust if necessary and shoot again.
The white balance should be set to tungsten if you're shooting in JPG mode or it can be left on auto with RAW as you can adjust this later.
Set the focus point manually. Just hold a magazine or book or similar sized object where the head of the torch is and let the camera focus. Then switch to manual, leaving the focus at that point.
Take the shot
Now you're ready to take the shot. Turn off any room lights, switch the torch on and pull it back and let go so it starts to swing. Gently throw it in a sideways direction to get a narrow oval pattern or a wider arc to get a more circular effect. Give the torch a few seconds to find a smooth shake-free path and open the camera's shutter.
Do a test run at f/8 and see if the light is bright enough. If the trail is dark open up the aperture to f/5.6 or f/4. If it's too bright stop down to f/11 or f/16.
Now comes the experimental part. Try different numbers of rotations, diferent speeds, and various angles to get variety. Also try adding coloured cellophane (Quality Street sweet wrappers are ideal) to get coloured paths. Cover the lens with a lens cap or black card while you change the colour wrapper. And change the direction of the torch swing for each colour.
If you have a multiple exposure mode you could take a shot for each colour and the camera will combine them. Unlike normal multiple exposures you don't need to compensate for the build up of exposures. Just keep the same full exposure for each swing.
The shot below was taken with a six frame multiple exposure and a short duration of 4 seconds was used for each of the loops. The red colour is the light coming through the back of the cheap torch. It was accidental, but I think it has enhanced the shot.