Digital Camera Tips > Fill Flash

Filling In With Flash

Add detail to your portraits with a little help from your flash

Most people use their flash at night to take a photo that isn't blurry.

How many people do you know who use their flash during the day? Unless you hang out with a crowd of photographers, probably not very many.

Use Flash to Reduce Shadows

You can use your flash even on a bright sunny day to reduce the intensity of shadows. This technique is most common when you are taking a portrait.

There are two extreme cases where fill flash can make a huge difference in your photo: when the subject is wearing a hat and when the sunlight is behind them.

Hat Shadow

When it's a sunny day and your subject is wearing a hat, the majority of their face can be in shadow. Depending upon how bright the sun is, you can lose all detail in the eyes and nose — the top half of the face becomes one dark mass.

When you use your flash in this instance, the shadow part of the face is lit, and detail reappears. Now you can see your subject's eyes in the finished photo, and capturing the eyes (and their expression) is an important part of portrait photography.

Silhouette

Maybe you've done this: you take a photo of a loved one with a sunset behind them. The sunset turns out great, but the subject of your portrait is a big shadow. Your subject has become a silhouette.

This happens because a sunset is relatively bright compared to the amount of light falling on your subject. If you adjust your camera to properly expose the subject, the background is substantially over-exposed.

Again, you can use your flash to illuminate your subject, while still keeping the sunset behind them properly exposed.

Fill Flash Example

The first photo is an example of a subject that is lit from behind. The strong backlight turns the primary subject into a silhouette. This is totally fine if it is the look you are trying to achieve. The second photo shows how fill flash illuminates the subject despite the strong backlight.

Example 1 - No Fill FlashExample 2 - Fill Flash
no fill flashfil flash

External Flash and Fill

If you're going to experiment a lot with fill flash, I recommend you use an external flash. External flash units give you more control over the amount of light emitted by the flash.

A lot of times, you don't want to blast your subject with fill light, you just want a small amount. Built-in camera flash units cannot typically be adjusted. They emit the same amount of light every time the flash goes off.

External flash output can be reduced, so that you have more control over the appearance of the image and just how much fill light you are adding to your photograph.