You can have a lot of fun with flashlights and photography. Here are 4 very simple photos I took to quickly demonstrate. You can get much more creative with time and imagination. Be sure to try these out in dark environments. No Photoshop is required for these photos, this is all done with your camera.
PHOTO TRICK 1
In this shot, I taped a mini flashlight behind the bulb. Then you simply play around with the length of time for the exposure. The easiest way is using the Tv mode on your DSLR. A few seconds should do the trick. Seconds are usually represented as double quotes (“), e.g. 3” is 3 seconds.
PHOTO TRICK 2
In this photo, you set your camera on a tripod. Ensure it is very dark. Set your camera to a long exposure such as several seconds. Then turn on your flashlight while aiming at the camera and move it around all while the camera is “taking the photo”. Turn the flash off when you have created whatever shape you want. Hopefully you were quick enough within the amount of time you allowed yourself during the long exposure.
You can achieve the next 2 example photos using longer exposure time. The easiest is if your DSLR supports Bulb mode. Bulb keeps the camera shutter open as long as you are holding the button. This is great for very long exposures. I personally use this a lot for astrophotography and fireworks. Here are 2 photos I took recently. I had my camera set to bulb mode and kept taking random shots trying to time it to the fireworks and experimenting with different exposure times. Generally you only need a few seconds.
If you have a friend helping you, they can be the one pressing the shutter release button on your camera. If you want to do it yourself, you can buy a very inexpensive shutter release cable. It would allow you to “hold” the shutter open while you are taking your shot.
PHOTO TRICK 3
This is where a bit of imagination goes a long way using a flashlight to selectively “paint” your photo. In this shot I setup my DSLR on a tripod and used a shutter release cable to hold my shutter open with the camera in Bulb mode. I stood in position 1, turned on the flashlight aiming it at my face, turned off the flashlight, moved to position 2, turned on the flashlight, turned it off, moved to position 3, turned on the flashlight, turned it off, then went to the camera and closed the shutter by sliding my shutter release cable button.
You need to be careful you don’t trip on anything in the dark. You can get away with a tiny amount of ambient light to see.
PHOTO TRICK 4
This photo is identical to photo 3 above, however I kept my body in the exact same position and simply moved my head. You need to keep it very still otherwise it can get blurry like on the left.
You will need to play around with your focus beforehand when you know where you will be standing. These tricks are much easier with someone else helping you however as demonstrated above, very possible to do it by yourself.
If you have a willing subject, it is fun to paint them with a flashlight while you are taking the photo. You can have them move their hands. Also fun is painting objects. You can take some wonderful photos of your home at night and use a flashlight to highlight certain aspects.
I hope this provides you with some fun things to try with your camera. It’s great to experiment now that we don’t need to worry about wasting film.