Taking Advantage of TTL Flash Photography
Generally, camera mounted TTL flash systems are better than pop up flash and tend to mix better with soft light. You know you have to use the flash if more than half of your subject is in shadow, and there are two distinct systems for using flash photography. Main flash or what is also known as main light is the technique of using your TTL flash to imitate the sun or provide a primary light source. Flash fill is the technique of using the flash to fill in the shadows and dark spots.
Flash fill is primarily used when shooting subjects outdoors. Whether it is birds, people, plants, or animal’s flash fill will help you bring each subject to life and bring it out of the background. Main flash is largely used when shooting at night or in dark spaces. Main flash tends to make the subject stand out from dark backgrounds, bathing them in soft light.
Using Main Flash
Controlling flash photography can be quite difficult because flash is an immediate explosion of light that can scare subjects (nocturnal animals) and create hard lines. When using your TTL flash as the main light source it is generally impossible to determine where the light is going to fall, and how it is going to look. If you have a model light on your camera (FUNC button on most D-SLR’s) push it down until the light comes on (release to shut off). This model light will help you figure out what the light is going to do before you take the picture. If you do not have this function on your camera you can attach a miniature flash light next to your TTL flash and it will give you the same effect.
Before you take the picture, look through the lens and determine how hard the shadow edges are. Generally when shooting a subject outdoors at night or in a darkly lit room it is best to create a soft ambient light. Bright light will create over-exposed highlights that create white spots in the photograph, making your shadows look even deeper. If you do end up with hard lines, and this is your intent than you are ready to start shooting, if not you will need to fill the shadow with another light source.
Using Flash Fill
Whether you are using a main light source or shooting subjects outdoors in natural light, there will be some point when you are going to want to use flash fill. With main flash, if your lines are too hard you will want to use flash fill. When shooting a subject outdoors, flash is used to fill in the dark areas and shadows. On one side your subject may be lit by the sun while the other is completely in shadow. If you don’t want to see this shadow you have to use the flash fill technique.
Once you decide that you need flash fill it’s only a matter of deciding how much. Test the light by dialing 2/3 stops in minus exposure until the unlit side is about 90% balanced with the lit side. The last 10% is a matter of skill and art and should be carefully determined. It’s impossible to tell you how to adjust the last 10% considering it takes experience and artistic aptitude to get the right light, but practice makes perfect.
Flash fill is primarily used in wildlife photography and outdoor portraiture but can help in a number of photographic situations. Developing flash and camera technology are making it easier and easier to achieve techniques that would other wise be very difficult, especially for the inexperienced. Flash can help add drama to any photograph but must be used carefully because it can also ruin a perfectly great shot. For the most part, without flash many subjects would be under-exposed, hidden amongst shadows. The idea is to get people to say wow, not “what is it?”.
