Fill light

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A typical three-point lighting setup with a shoulder or back-side lamp to create contrast between the background and center object so as to give a three-dimensional appearance. 3 point lighting.svg
A typical three-point lighting setup with a shoulder or back-side lamp to create contrast between the background and center object so as to give a three-dimensional appearance.

In television, film, stage, or photographic lighting, a fill light (often simply fill) may be used to reduce the contrast of a scene to match the dynamic range of the recording media and record the same amount of detail typically seen by eye in average lighting and considered normal. From that baseline of normality using more or less fill will make shadows seem lighter or darker than normal which will cause the viewer to react differently, by inferring both environmental and mood clues from the tone of the shadows.


Natural skylight fill is omnidirectional and diffuse, with lower rate of inverse-square fall-off than artificial sources. A common artificial lighting strategy which creates an overall appearance similar to natural fill places the fill light on the lens axis so it will appear to cast few if any shadows from the point of view of the camera, which allows the key light which overlaps it to create the illusion of 3D in a 2D photo with the same single source patterns typically seen with natural lighting where the sun acts as key light and the skylight as fill. The use of centered near-axis "neutral" fill also prevents dark unfilled voids in the lighting pattern which can occur on faces if cheeks or brows block the fill source.

Lighting deliberate use of light to achieve a practical or aesthetic effect

Lighting or illumination is the deliberate use of light to achieve practical or aesthetic effects. Lighting includes the use of both artificial light sources like lamps and light fixtures, as well as natural illumination by capturing daylight. Daylighting is sometimes used as the main source of light during daytime in buildings. This can save energy in place of using artificial lighting, which represents a major component of energy consumption in buildings. Proper lighting can enhance task performance, improve the appearance of an area, or have positive psychological effects on occupants.

Key light first light in a photographic or filmmaking lighting scheme

The key light is the first and usually most important light that a photographer, cinematographer, lighting cameraman, or other scene composer will use in a lighting setup. The purpose of the key light is to highlight the form and dimension of the subject. The key light is not a rigid requirement; omitting the key light can result in a silhouette effect. Many key lights may be placed in a scene to illuminate a moving subject at opportune moments.

The positioning of the fill affects the overall appearance of the lighting pattern. When a centered fill strategy is used the ratio is created by overlapping the key light over the foundation of fill. A key source of equal incident intensity to the fill, overlapping the even fill, will create a 2:1 reflected ratio (1 key + 1 fill over 1 Fill) = 2:1. The same two equal incident strength sources placed on opposite side of a face will work to cancel each other out creating overall dimensionally flat appearance with dark unfilled voids in low areas neither light reach. Part of the learning curve with lighting is experimenting with various highlight:shadow reflected ratios and fill positions, comparing them to baselines and reactions to what is seen by eye, and in doing that learning how to trigger the same reactions in the mind of the viewer.

Lighting ratio in photography refers to the comparison of key light to the fill light. The higher the lighting ratio, the higher the contrast of the image; the lower the ratio, the lower the contrast. Since the lighting ratio is the ratio of the light levels on the brightest lit to the least lit parts of the subject, and the brightest lit are lit by both key (K) and fill (F), therefore the lighting ratio is properly (K+F):F although for contrast ratios of 4:1 or more, then K:F is sufficiently accurate.

Ratio measurement and notation

In cinematic and stage work where many lights are used the numerical ratios are typically set per incident strength of each source and referenced similarly. The Highlight:Shadow ratio convention long used in portraiture is based indeed on the reflected light the camera records when the sources overlap. Very early analog ratio meters consisted of a card with two holes, one blank and the other covered with a strip of neutral density. The blank hole would be held over the shadow side of the face and the hole with the filters over the highlight side and adjusted until the appearance matched visually. Each .30 difference in neutral density was equal to a 2x difference in reflected light. In the case of two equal sources overlapping in a key over centered fill strategy the incident strength is 1:1 between them but the overlap creates a 2:1 reflected ratio. So when expressing ratios it is important to make the distinction between incident and reflected to avoid confusion.

Negative fill / subtractive lighting

In cases where the fill light is desired to be darker than what is available without artificial means, a flag or frame may be used to block ambient light and thereby provide what is called negative fill. [1]

A flag is a device used in lighting for motion picture and still photography to block light. It can be used to cast a shadow, provide negative fill, or protect the lens from a flare. Its usage is generally dictated by the director of photography, but the responsibility for placing them can vary by region, usually devolving to either the gaffer and electricians or the key grip and lighting grips.

In cinematography, butterflies are structures on which materials are mounted so to control lighting in a scene or photograph. Materials commonly used on butterflies include: flags, nets, and diffusions for the purposes of blocking, dimming, and scattering light respectively. In general, butterflies are used only for very large materials, while smaller sizes are usually sewn on to portable frames for ease of placement and storage.

In omnidirectional open shade or an overcast day where the light creates few highlight or shadow clues regarding 3D blocking the light on one side will have the net effect of making the light from the other direction the more dominant "key" vector in the lighting pattern using a process also referred to as "subtractive lighting".

Reflectors as fill sources

An alternative to using a direct light source as a fill is to re-direct or "bounce" the key light towards the subject by using a reflector. When used with artificial key light it can be difficult to place a reflector where it can both catch and reflect the light and have it bounce back onto the subject at the ideal "neutral" near-axis angle, often resulting in dark, underfilled areas in the lighting pattern. This is less of a problem outdoors where light usually comes from many directions.

Reflector (photography) reflective surface used to redirect light towards a given subject or scene, used in photography

In photography and cinematography, a reflector is an improvised or specialised reflective surface used to redirect light towards a given subject or scene.

Spill fill

The term "spill fill" refers to fill light which results from the footprint of light sources bouncing off surfaces in the shooting environment. It can, if not observed and understood, lead to erroneous assumptions about lighting strategies and modifier choices. For example, a difference between a softbox and shoot-through umbrella of identical size used in a small reflective space is that the softbox is designed to limit spill and the shoot through umbrella to maximize it. The umbrella will appear to "wrap" the light more, but in terms of actual cause and effect the "wrap" effect results from the light bouncing off ceiling and walls back into the shadows created by the key light from many different directions.

An advantage of a dedicated studio space vs. location shooting is that the "spill fill" becomes a predictable variable in the overall lighting strategies. Some studio photographers aim their dedicated fill source at a white wall behind the camera near the ceiling to intentionally create omnidirectional "wrap around" fill similar to natural skylight and eliminate the reflection "catchlight" a direct fill source will create in the eyes.

With location shooting the spill fill variable will cause the same lighting strategy to produce different result. Outdoors there is no spill fill created by artificial sources which is why cap style speedlight modifiers perform differently outdoors and large indoor spaces which reflect very little spill fill. Skylight outdoors is "spill fill" in the sense it reflects the light of the sun in a way the photographer can't control unless a reflector or flash is used to modify the three f/stop difference in brightness that typically occurs between direct sun and shade.

Cause and effect

A systematic approach for visualizing the cause and effect is to start from a baseline set-up with the testing done outdoors at night or in a large darkened indoor space where there will be no reflected "spill fill". Set a camera on a tripod at the aperture desired for depth-of-field and start with just the fill source located centered and chin level to a subject facing the wearing black and white textured clothing.

Raise fill power until detail is seen in the black clothing. The nose on front of the face will be observed to be lighter than the ears due to the inverse-square fall off of the fill source and it will create a light-to-dark gradient. The contrast of the gradient can be altered by changing the distance of the fill light from the subject. With most recording media (B&W negative being the exception) the white clothing will not be correctly exposed when the fill light is adjusted based on shadow detail. That problem is solved by adding the key light which for this exercise should be placed 45° above the eye line and 45° to the side of the nose of the subject facing squared to the camera.

Raise the power of the off-axis key light until the white clothing is exposed correctly, appearing white but also retaining texture detail. The combination of overlapping key over centered fill works together to change scene contrast to exactly fit the dynamic range of the recording media. Due to the way the photographic process is engineered the response between the black and white extremes in the scene range will be reproduced in a way similar to human perception and the image will look "seen by eye normal" in the flash lit foreground. But if the exercise is done outside where there is no ambient light or bounced spill-fill the rapid fall off and actual footprint of the sources will be seen.

The ratio of key vs. fill in incident terms needed to reproduce both ends of the tonal range on the subject will vary with the dynamic range of a digital sensor or transparency film. In the case of negative / print systems the limiting factor will be the range of the print material, or if the negative is scanned the dynamic range of the scanner. The ratio can be determined numerically after the visual evaluation based on shadow detail for fill and highlight detail for key by measuring each light separately from subject position with an incident meter aimed at the fill then the key light.

From that "baseline" experiment using centered fill and fitting scene range to output media a photographer can systematically change one variable at a time and observe how that affects appearance, such as fill position (watching or shaded fill areas), changing the key:fill ratio using the same pattern, or using different modifiers on the fill source. Repeating the same tests indoors where light bouncing around the room is a factor will make the photographer aware of how the shooting environment will change both the appearance and numerical ratio the same standard "baseline" set-up produced when there was no "spill fill".

Understanding how the cause and effect of the technical variables affect viewer emotional reaction to the content under the lights is what equips the photographer with the skill to pick the lighting strategy and modification techniques which will best meet the goal for how the target audience will react emotionally photograph due to the clues the lighting create about the environment and mood of the subjects.


With the sunlight coming from the right and behind the model, a shoot-through umbrella (on camera left) was used to illuminate her. Model in California Desert.jpg
With the sunlight coming from the right and behind the model, a shoot-through umbrella (on camera left) was used to illuminate her.

Shoot Thru Umbrella (Shoot-Through) is where light passes through an umbrella as opposed to being reflected by it. The umbrella acts as a light diffuser, softening the light and allowing it to spread over the subject evenly. [2]

See also

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Daylighting is the practice of placing windows, skylights, other openings, and reflective surfaces so that sunlight can provide effective internal lighting. Particular attention is given to daylighting while designing a building when the aim is to maximize visual comfort or to reduce energy use. Energy savings can be achieved from the reduced use of artificial (electric) lighting or from passive solar heating. Artificial lighting energy use can be reduced by simply installing fewer electric lights where daylight is present or by automatically dimming/switching off electric lights in response to the presence of daylight – a process known as daylight harvesting.

Light meter photographic equipment

A light meter is a device used to measure the amount of light. In photography, a light meter is often used to determine the proper exposure for a photograph. Typically a light meter will include either digital or analog electronic circuit, which allows the photographer to determine which shutter speed and f-number should be selected for an optimum exposure, given a certain lighting situation and film speed.


In lighting for film, theatre and still photography, a cucoloris is a device for casting shadows or silhouettes to produce patterned illumination. It is normally referred to as a cookie or sometimes as a kook or a coo-koo. The cucoloris is used to create a more natural look by breaking up the light from a man-made source. It can be used to simulate movement by passing shadows or light coming through a leafy canopy.

Contre-jour photographic technique

Contre-jour is a photographic technique in which the camera is pointing directly toward a source of light and an equivalent technique of painting. It was also used in paintings prior to its use in photography, where the shadows would fall to the left on the left, to the right on the right and forward in the lower centre. The edges of the subject would show surprising colour effects.

Grip (job) occupation in film and TV production

In the U.S. and Canada, grips are technicians in the filmmaking and video production industries. They constitute their own department on a film set and are directed by a key grip. Grips have two main functions. The first is to work closely with the camera department to provide camera support, especially if the camera is mounted to a dolly, crane, or in an unusual position, such as the top of a ladder. Some grips may specialize in operating camera dollies or camera cranes. The second main function of grips is to work closely with the electrical department to create lighting set-ups necessary for a shot under the direction of the director of photography.

Grips' responsibility is to build and maintain all the equipment that supports cameras. This equipment, which includes tripods, dollies, tracks, jibs, cranes, and static rigs, is constructed of delicate yet heavy duty parts requiring a high level of experience to operate and move. Every scene in a feature film is shot using one or more cameras, each mounted on highly complex, extremely expensive, heavy duty equipment. Grips assemble this equipment according to meticulous specifications and push, pull, mount or hang it from a variety of settings. The equipment can be as basic as a tripod standing on a studio floor, to hazardous operations such as mounting a camera on a 100 ft crane, or hanging it from a helicopter swooping above a mountain range.

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Low-key lighting

Low-key lighting is a style of lighting for photography, film or television. It is a necessary element in creating a chiaroscuro effect. Traditional photographic lighting, three-point lighting uses a key light, a fill light and a back light for illumination. Low-key lighting often uses only a key light, optionally controlled with a fill light or a simple reflector.

Three-point lighting Lightning technique

Three-point lighting is a standard method used in visual media such as theatre, video, film, still photography and computer-generated imagery. By using three separate positions, the photographer can illuminate the shot's subject however desired, while also controlling the shading and shadows produced by direct lighting.

Fill flash

Fill flash is a photographic technique used to brighten deep shadow areas, typically outdoors on sunny days, though the technique is useful any time the background is significantly brighter than the subject of the photograph, particularly in backlit subjects. To use fill flash, the aperture and shutter speed are adjusted to correctly expose the background, and the flash is fired to lighten the foreground.

High-key lighting

High-key lighting is a style of lighting for film, television, or photography that aims to reduce the lighting ratio present in the scene. This was originally done partly for technological reasons, since early film and television did not deal well with high contrast ratios, but now is used to suggest an upbeat mood. It is often used in sitcoms and comedies. High-key lighting is usually quite homogeneous and free from dark shadows. The terminology comes from the higher balance in the ratio between the key light and the fill light in a traditional three point lighting setup.

Rembrandt lighting lighting technique that is used in studio portrait photography

Rembrandt lighting is a lighting technique that is used in studio portrait photography. It can be achieved using one light and a reflector, or two lights, and is popular because it is capable of producing images which appear both natural and compelling with a minimum of equipment. Rembrandt lighting is characterized by an illuminated triangle under the eye of the subject on the less illuminated side of the face. It is named for the Dutch painter Rembrandt, who often used this type of lighting.

Hard and soft light

Hard and soft light are different types of lighting that are commonly used in photography and filmmaking. Soft light refers to light that tends to "wrap" around objects, casting diffuse shadows with soft edges. Soft light is when a light source is large relative to the subject; hard light is when the light source is small relative to the subject.

Backlighting (lighting design) lighting

In lighting design, backlighting is the process of illuminating the subject from the back. In other words, the lighting instrument and the viewer face each other, with the subject in between. This creates a glowing effect on the edges of the subject, while other areas are darker. The backlight can be a natural or artificial source of light. When artificial, the back light is usually placed directly behind the subject in a 4-point lighting setup. A back light, which lights foreground elements from the rear, is not to be confused with a background light, which lights background elements.

Portrait photography photography genre

Portrait photography or portraiture in photography is a photograph of a person or group of people that captures the personality of the subject by using effective lighting, backdrops, and poses. A portrait picture might be artistic, or it might be clinical, as part of a medical study. Frequently, portraits are commissioned for special occasions, such as weddings or school events. Portraits can serve many purposes, from usage on a personal Web site to display in the lobby of a business.

Available light

In photography and cinematography, available light or ambient light refers to any source of light that is not explicitly supplied by the photographer for the purpose of taking photos. The term usually refers to sources of light that are already available naturally or artificial light already being used. It generally excludes flashes, although arguably flash lighting provided by other photographers shooting simultaneously in the same space could be considered available light. Light sources that affect the scene and are included in the actual frame are called practical light sources, or simply practicals.

Monte Zucker M.Photog.Cr., Hon.M.Photog., API, F-ASP was an American photographer. He specialized in wedding photography, entering it as a profession in 1947. In the 1970s he operated a studio in Silver Spring, Maryland. Later he lived in Florida.

Photographic lighting illumination of scenes to be photographed

Photographic lighting is the illumination of scenes to be photographed. A photograph simply records patterns of light, color, and shade; lighting is all-important in controlling the image. In many cases even illumination is desired to give an accurate rendition of the scene. In other cases the direction, brightness, and color of light are manipulated for effect. Lighting is particularly important for monochrome photography, where there is no color information, only the interplay of highlights and shadows. Lighting and exposure are used to create effects such as low-key and high-key.


  2. Arias, Zach. "Shoot Through Umbrella vs. Softbox". Archived from the original on 31 March 2013. Retrieved 18 February 2013.