This is my first experience with this activity. The camera is set to "bulb" mode and my shutter release cable has a 'locked' position allowing the user to leave the aperture open indefinitely. The light source is a simple led flashlight. I have it tied to a lanyard which is swung for part of the exposure. It's fun to see what shapes can be developed.
Fiddle Leaf FigMarch 5light paintingpad