Physiogram's are rather old actually, dating back to the 19th century, and have become rather lost in time, so here is how I created these interesting photographs.
Step 1: Setting Up the Equipment
Note: If you're like me you have a bunch of really small single led's lying around. These do not have enough weight by themselves to create smooth physiograms, and therefore need to be tied down with something a little heavier. Anything will work, but make sure you can secure it safely so you don't have objects falling on your camera lens.
Now tie the other end of the string to something attached to the ceiling, hanging down anywhere from 1 to 2 meters from the ceiling (this will be adjusted later). I found my ceiling fan to be perfect for this.
Step 2: Place Your Camera and Adjust Your Frame
Take the led (turned on, other lights off) and swing it in the air, in a circular motion. Doing this during a long exposure (at least 15 seconds, a camera on bulb mode if preferable) will create the physiogram. Make sure to take a couple test shots, adjusting either the length of the string or the zoom on your lens as necessary to make sure the physiogram fills the whole frame.
Experiment with different throwing patterns, making the path more line-like or more circle-like, and see what you like. There are also many people who experiment with moving the camera under the moving lights, and multiple physiograms on top of each other. The possibilities are almost endless.
Step 3: Editing the Photo
This step requires an image editor, I use photoshop and this is what I will describe, I'm sure it can also be done in GIMP too. Use the photoshop magic wand tool to select the actual physiogram. You may have to mess with the tolerance to get the picture right, but this is all you should have to do. Once you have selected the physiogram you must invert the selection so everything but the physiogram is selected.
Once you have done this you must delete everything but the physiogram, and then place it over a black background. Sometimes messing with brightness and contrast before using the magic wand tool can help.
Step 4: Done!
Now that you have that knowledge, you can use it in even more advance long exposure/light painting projects, such as making a light painting animation.
Or you can continue to experiment in the world of physiograms, there is much more than can be done with this art, I have only just scratched the surface with my photos.
Thank you for viewing this and comment if you have any questions. Also if you enjoyed it and you think someone else you know might then please find it in your kind hearts to spread this around, I want to see an inrush of physiograms on flickr.