A friend told me about this photography method called Light Writing and so I decided to try the experiment for myself. You can use any kind of camera, as long as you can set the shutter speed manually. Just go outside after dark, or you can use a room in your house, you just have to be in pitch darkness. Next, have a friend go into the frame with a flashlight and make different motions, such as shape outlines, words, or even just free-style movements. Anything you want to be written in the photo with the light. When you get ready to take picture, set your camera to a slow shutter speed. This will allow for the image to be burned into the film or picture for a longer period of time, thus giving you a solid line of light.
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It is best to keep the camera as still as possible, that way the background does not get fuzzy as seen below. A tripod would probably work best.
Although if you do try moving the camera while the shutter is open, it helps your light to show up throughout the entire image, instead of in just one area. So if the background is dark enough, you can't tell whether or not it is fuzzy or blurry.
These were just a test try. I plan on trying it again and hopefuuly being able to write actual words with the light. And I need to do this when it's just a bit darker outside, as the background seems lighter than it actually was outside.