Light Painting- An Easy Bonfire Night Science Experiment
Don’t let the long winter nights get you down! Try out our light painting experiment this Bonfire Night to lighten things up
Bonfire Night has changed a lot since the Gunpowder Plot- today it’s a huge celebration of thrilling, explosive chemistry!
Chemistry has always been about making things flash, fizz and bang! So we’ve planned an artistic STEM experiment you can try out this Bonfire Night.
As the nights get longer and longer, why not try light painting? Light paintings are a creative way to combine chemistry and technology to create a unique piece of art! This is also an experiment in photography, you’ll find out what a long-exposure photo is, what changing shutter speed does and how cameras react to light.
What is Light Painting?
In this bonfire night experiment you create drawings by light painting. Light paintings is a technique where you use a moving light source (like a sparkler or a torch) when taking a picture with a long exposure to draw in mid air. You can see a smiley face we drew with a torch above.
A picture with a long exposure means your camera takes in light for a much longer time than usual. This means as you move your torch or sparkler it’s path will blur and get traced out in the picture. The result is one long pattern you can use to create pieces of art.
Use a sparkler as your light source to add a bonfire night spin, and to understand the chemistry of fireworks!
Getting set up
THE SAFTEY BIT!
Bonfire Night usually involves burning things which makes it a dangerous place for a young scientist. We won’t be asking you to light any rockets tonight, but you can use a sparkler for this experiment (or a torch if you prefer).
If you’re using a sparkler ask a responsible adult for help. Always have a bucket or large bowl of water to put sparklers in once they are finished with.
Your camera needs a setting on it called “shutter speed”. For light painting, need a very slow shutter speed to work. In our examples we used a digital camera to do it. We used shutter speeds of 1 second and slower to make our light paintings
Using a smart phone camera can be tricky- try downloading an app that lets you. There are apps like Slow Shutter Cam which work well on iPhone, and there are also plenty of free alternatives and ones available on the Google Play Store.
Otherwise, any old digital camera you used for holiday snaps will work fine too! They usually have a shutter speed option, you might need to look in the manual to find it.
How to do it
Make sure you do this Bonfire Night experiment outdoors if you’re using a sparkler, and for best results do it when it’s dark. A dark background helps the light from your sparkler or torch stand out.
1) First of all, practise what shape you want to draw out. Keep it simple though- the very best results come from easy to draw patterns. Try drawing out different shapes, or the initials of your name.
2) Now set up your camera. You’ll need a shutter speed of around 1 second or more. This means light will hit your sensor for a full second before it finishes creating the picture.
3) Place the camera somewhere steady, put it on a tripod (if you’ve got one), a table or give it to someone with very steady hands! At very slow shutter speeds, any knock or shake will make you picture too blurry. You’ll also need a willing assistant who can press the shutter button for you, or put you camera on a timer.
4) Light your sparkler or torch and start to draw out the shape. Ask your friend to press the button or wait for the timer on the camera to go off. Take as many photos as you can whilst your sparkler goes on!
If you’re using a torch, you can practice and take as many as you like. Once you’re done, have a look at the photo. Here’s our attempt at drawing a star!
How else can I try this experiment?
If it’s a rainy Bonfire Night this year, or you’ve ran out of sparklers, don’t worry! If you use a torch instead and you can do this experiment indoors. You can even during the day time if you keep your blinds shut!