While in training as a Police Forensic Identification Technician, I learned a fascinating technique for illuminating large areas at night, with only a single ordinary flash unit. The idea behind us learning and practicing this technique was that there would be times in our careers as “Ident” men and women that we would be out on some highway at three o’clock in the morning, photographing an accident, or out in a field photographing a crime scene.
This technique, called “Painting with Light” would allow us to record the entire scene in one photo, which would give a much clearer picture of the crash than several individual photos. To allow us to practice, the Police College sent us out to the old runway behind the college one night. The photography teacher and the fingerprint teacher placed their cars several hundred feet apart on the runway and then told us to photograph both cars in the same photo.
The technique is surprisingly simple. A camera with manual control of the shutter speeds and aperture is required, as well as a flash unit that has manual or partially automatic control. You can’t use through the lens flash metering for this trick. You’ll also need a flashlight to be able to see what you’re doing. The camera is set up on a tripod, with the main subjects of interest in the center of the frame if possible. First make sure the camera is focused on the nearest subject of interest.
You may need to shine the flashlight on it to focus properly. If you can’t do this, estimate the distance to the object and set the lens manually using the distance markings on the lens barrel. Now the shutter is locked in the open position, either using a locking cable release with the camera on the “bulb” setting (‘B’ on the camera’s shutter speed dial), or, if it’s an older or professional camera, placing it on the “T” setting (for time exposure).
Now you need to draw an imaginary line right down the center of the scene and decide how far on each side of this line you need to illuminate. Let’s say you want to illuminate 15 feet on either side of the line (that’s 30 feet total across the width of the scene). Put your flash unit on manual, or on an automatic setting which will allow you to illuminate for 15 feet. If you’re on manual, check your ISO setting to be sure it’s correct, then set it up so that it will easily illuminate 15 feet.
By this, I mean that if your flash unit has several manual ranges, such as full power, one-half power, one-quarter power, etc., make sure that whatever setting it’s on, it will cover 15 feet at whatever aperture you want to use. Depending on how far you are from the first subject in the scene, you may need to use a smaller aperture to get the depth of field you need to keep everything in focus.
So, for example, say you are going to use f8 on your lens. Set your flash so that if you were photographing an object 15 feet away with the flash on top of your camera, with the lens set at f8, it would be properly exposed. If you are using one of the automatic ranges, simply choose the one that has the aperture you want to use, and which will cover at least 15 feet sufficiently.
Now, the fun part. Starting at the camera, holding the flash up high, manually fire the flash 5 times, directly at the scene. Now, go out 17 or 18 feet from the centerline of your scene on either side, and flash 5 times again (directly beside the camera, but pointing the flash towards the centerline, on an angle pointing away from the camera). Now, take 5 steps down the “sideline”, about 17 or 18 feet away from the centerline at all times.
Every 5 steps, hold the flash up above your head and fire it 5 times at a slightly downward angle, again making sure the flash head is pointed slightly away from the camera. Go all the way to the end of the scene, and cross over to the other side, repeating the process all the way back to the camera. Keep in mind you never want the flash facing the camera, or you will get a huge “white-out” in the picture.
The only exception is if you wish to “halo” an object in the scene, in which case you can crouch down behind the object and fire the flash once or twice. The flash should not be directly visible to the camera. For the sideline exposures, the flash should always be angled away from the camera, but toward the centerline. As long as the flash is set for the 15-foot distance at whatever aperture you are using, the picture will be properly exposed.
I know it sounds hard to believe, but it works! You will need to experiment a bit with the number of times you flash at each location, depending on the darkness of the area, and the power of your flash unit. Obviously, an area with a lot of ambient light will not need as much illumination as a pitch-black area. I used this technique on several accident scenes, one of which extended over 100 yards down a completely pitch black country lane.
There was debris as close to the camera as 25 feet, and vehicles as far away as 100 yards, and all of them were clearly visible in the resulting photo. I hope you can find more pleasant ways to use this technique, and I’m sure you’ll be amazed at how good the photos turn out with a little practice. Happy shooting!