Red eye is a phenomenon that has affected every photographer at some time or another. It is the glowing red eyes caused when the light from a flash is reflected off the blood vessels in your subjects’ retina. Red eye may ruin even the best photo. The closer the flash is to the lens, the more likely there will be red eye (which is why red eye is a very common problem on point and shoot cameras). As the distance between the flash and the lens increases, the chance of red eye decreases.
- Use color gels. Gels are polyester sheets that are a specific color. The name comes from the thin dried sheets of colored gelatin used in the early days of theater lighting. Placing the gel in front of the light source changes the color of the light produced. Matching the light being output from the flash to the color of the ambient light is very important. When shooting inside, other light sources ought to be taken into account. When two different types of light are used to light the same scene, problems arise. The camera cannot figure out what the white balance should be. The answer to this is to place a gel in front of the flash so that the color of the light that the flash outputs matches the color of the ambient light in the scene. Yellow gels balance out the light from incandescent lights found in most homes, and green gels balance out fluorescent light. Lumiquest produces an FX Color Gel pack and holder that you can purchase for under $30.
- Lower the flash output. The light from the flash might overpower the natural light in the scene, creating harsh flat light and hard flash shadows. One of the simplest ways to fix this is to lower the amount of light the flash produces, the flash output, until it is closer to the natural light.
- Remove the flash from the camera. Removing the flash from the camera means that the flash can be set at a different angle to the camera, creating a more natural light. Some cameras, especially the latest DSLRs allow you to remove the flash, whereas in compact cameras you can usually disable the flash function manually.
Have a look at other articles describing the influence of lighting conditions on photography:
The Color of Light, The Diffusion of Light, The Intensity of Light, Light Direction, Light types,