Basics for newcomers to fill light

Fill light definition

In photography, fill light is not as bright as key light. But it is just inferior to the key one in three-point lighting, in which backlight is the third. Light engenders brightness as well as shadow. When the light falls onto one side of an subject, the other side of the subject will become dark. Fill lighting is used to fill in that shadow. Using key light and fill light appropriately can perfect a shot and help create desired atmosphere.


The most important function of fill light is filling in the shadow created by the key one and presenting the details and shapes of the subject. It contributes to decreasing the contrast of a scene and softening the facial outline. With key and fill light, the shot will be much more vivid and more close to the scene human eyes see in real life. So using LED fill light for photography is a good choice.

Filmmakers and photographers are skilled at using various lighting to affect the mood of audience. Fill light in film plays a significant role in creating the mood of a scene, for it determines the depth, shadow and contrast. The lower brightness the light emits, the higher contrast is. High contrast and harsh shadow matter when creating a serious mood.

Two main types of fill lighting

There are several types of fill lighting. Different light source may result in different lighting effects. Choosing a suitable type is very important because it influences the realization of desired scene. Here are two main types of sources.

1. LED fill light

LED fill light is the most common one. Nowadays, many LED lights are capable of adjusting the intensity and the angle, which provides ease for different requirements of photographing. The controllability of LED makes it become the first choice for photographers. Some LED lights are equipped with portable battery that it can work outside for a long time.

Use LED fill light COLBOR PL5

2. Reflectors

Reflector is another common means to create light. The reflected light is basically determined by the material of reflectors and the distance from the subject. There is a disadvantage of it that sometimes the light provided by it is insufficient to fill in the shadow.

How to use a fill light?

For the sake of making good use of a light to improve the quality and the mood of a shot as far as possible, there are several things should be concerned.

1. Choose the right position

The first step to use fill light in photography is choosing a correct place to position it in the three-point lighting setup. A fundamental position technique is placing it opposite to the main light. And the angel between the supplementary lighting and the camera is usually similar to the one between the main one and the camera. In this way, the shadow can be approximately filled. When positioning the light, please make sure that it doesn’t bring out a second shadow. If there is a second shadow, that means the intensity is too strong. In this situation, the illumination should be dimmed or moved away from the subject.

2. Adjust the lighting intensity

Generally speaking, the intensity of fill-in light should not be as strong as the main lighting. The intensity is determined by what mood the photographer want. When it comes to lighting intensity, the concept of lighting ratio should not be missed.

Basically, it refers to the comparison that generated by key fill light. When the fill light is equally bright like the key one, the lighting ratio is 1:1. When the key is three times brighter than than the fill , the ratio is 4:1. Different ratio can be used to create different mood of a scene. The contrast varies with the lighting ratio. High lighting ratio helps create a serious and tense atmosphere while low lighting ratio helps create a relatively relaxed atmosphere. For instance, 8:1 lighting ratio is frequently used in horror movies to create a thrilling scene.

3. Remain some shadow

Although photography fill light is used to fill in the shadow generated by the key lighting, remaining some shadow is sometimes better than completely removing the shadow from the scene. Shadow can present a sense of depth, which makes the shot more stereoscopic and real.Imagine that you are going to take a long journey or shoot outdoors for a long time. It’s inconvenient to carry a traditional large lighting. In this situation, pocket light will be a good choice. When you go hiking, boating or camping, a suitable pocket light is a great help.