I have been using this effect to create the whole LightSpin project. I used it mostly because the light gets very concentrated, so I had less problem with light spill on the walls.
Portuguese version, by Fabio Meideiros
Spanish version, by Guillermo Castellanos
French version, by Laurent Wittmann
If you'd like to translate this tutorial in another language, you can download the psd file.
This is the light-painting effect I used to create the LightSpin project, a bullet-time / stop-motion documentary made in Montréal with contemporary dancers
This is Monica Dogra, on a picture from the light-painting music video Suspended I did in India in 2013:
***UPDATE*** One year after LightSpin, I started to work again with Kim Henry to improve the technique, and we got back to this same effect just to make sure we're still able to reproduce it. We're quite happy about the result :)