Reflector (photography)
Encyclopedia
In photography
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...

 and cinematography
Cinematography
Cinematography is the making of lighting and camera choices when recording photographic images for cinema. It is closely related to the art of still photography...

, a reflector is an improvised or specialised reflective surface used to redirect light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

 towards a given subject or scene.

Types

Apart from certain highly specialized components found in enlarger
Enlarger
An enlarger is a specialized transparency projector used to produce photographic prints from film or glass negatives using the gelatin silver process, or from transparencies.-Construction:...

s, projectors
Slide projector
A slide projector is an opto-mechanical device to view photographic slides. Slide projectors were common in the 1950s to the 1970s as a form of entertainment; family members and friends would gather to view slide shows...

 and scanners
Film scanner
A film scanner is a device made for scanning photographic film directly into a computer without the use of any intermediate printmaking. It provides several benefits over using a flatbed scanner to scan in a print of any size: the photographer has direct control over cropping and aspect ratio from...

, photographic reflectors fall into two main groups:

Lamp reflectors

Similar to a domestic lampshade
Lampshade
A lampshade is a fixture that covers the lightbulb on a lamp to diffuse the light it emits. Conical, cylindrical and other forms on floor-, desk- or table top-mounted as well as suspended lamp models are the most common and are made in a wide range of materials. The term can also apply to the...

, these reflectors are fixed to an artificial light source (for example, a filament bulb or flash tube) to direct and shape the otherwise scattered light, reflecting it off their concave inner surfaces and directing it towards the scene to be photographed. Although there are a large number of variants, the most common types are:
  • spherical, short-sided, giving a relatively broad spread of light;
  • parabolic
    Parabolic reflector
    A parabolic reflector is a reflective device used to collect or project energy such as light, sound, or radio waves. Its shape is that of a circular paraboloid, that is, the surface generated by a parabola revolving around its axis...

    , providing a tighter, parallel
    Parallel (geometry)
    Parallelism is a term in geometry and in everyday life that refers to a property in Euclidean space of two or more lines or planes, or a combination of these. The assumed existence and properties of parallel lines are the basis of Euclid's parallel postulate. Two lines in a plane that do not...

     beam of light.

The reflector factor is the ratio of the illumination provided by a lamp fitted within a reflector to the illumination provided without any reflector fitted. A matte reflector will typically have a reflector factor of around 2, due to its more diffuse effect, while a polished or metallic-finished reflector may have a factor of up to 6.

Board reflectors

Also known as plane
Plane (mathematics)
In mathematics, a plane is a flat, two-dimensional surface. A plane is the two dimensional analogue of a point , a line and a space...

 reflectors, "flats" or bounce boards, this kind of reflector is located independent of a light source; the light is reflected off its surface, either to achieve a broader light source, or control shadows and highlights, or both. This kind of reflector generally has a very low reflectivity factor that varies widely according to surface texture and colour. As a result, it is most commonly used to control contrast
Contrast (vision)
Contrast is the difference in visual properties that makes an object distinguishable from other objects and the background. In visual perception of the real world, contrast is determined by the difference in the color and brightness of the object and other objects within the same field of view...

 in both artificial and natural lighting
Lighting
Lighting or illumination is the deliberate application of light to achieve some practical or aesthetic effect. Lighting includes the use of both artificial light sources such as lamps and light fixtures, as well as natural illumination by capturing daylight...

, in place of a fill light
Fill light
In television, film, stage, or photographic lighting, a fill light may be used to reduce the contrast of a scene and provide some illumination for the areas of the image that are in shadow...

 or "kick" light. In this case, light "spilling" from the main ambient or key light illuminating a scene is reflected back into the scene with a varying degrees of precision and intensity, according to the chosen reflective surface and its position relative to the scene.

Reflectors may also be used as a means of increasing the size of the main light source, which may (or may not) retain a direct path to the scene. By positioning a board reflector close to a light source, its effective size can be increased by "bouncing" the light off it. A very common example of this technique is the traditional umbrella reflector, typically having a gold, silver or matte white interior onto which a lamp fitted with a circular reflector is projected, providing a broad, soft illumination. The lamp faces away from the scene to be photographed, allowing only reflected light to be thrown forward.

Techniques with board reflectors

Reflectors vary enormously in size, colour, reflectivity
Reflectivity
In optics and photometry, reflectivity is the fraction of incident radiation reflected by a surface. In general it must be treated as a directional property that is a function of the reflected direction, the incident direction, and the incident wavelength...

 and portability. In tabletop still life photography
Still life photography
Still life photography is the depiction of inanimate subject matter, most typically a small grouping of objects. Still life photography, more so than other types of photography, such as landscape or portraiture, gives the photographer more leeway in the arrangement of design elements within a...

, small mirrors and card stock are used extensively, both to reduce lighting contrast and create highlights on reflective subjects such as glassware and jewelry. Larger-scale subjects such as motor vehicles require the use of huge "flats", often requiring specialised motorized winches to position them accurately.
Location photography calls for much more portable materials and a large range of lightweight, folding reflectors are commercially available in a variety of colors.

Bounce lighting

Photographers make regular use of walls, ceilings and even entire rooms as reflectors, especially with the interior of buildings which may lack sufficient available light
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...

. Often known as "bounce flash" photography but equally common with tungsten
Tungsten
Tungsten , also known as wolfram , is a chemical element with the chemical symbol W and atomic number 74.A hard, rare metal under standard conditions when uncombined, tungsten is found naturally on Earth only in chemical compounds. It was identified as a new element in 1781, and first isolated as...

 lights in cinematography, the area to be photographed is lit by walls off-camera, which then provide illumination similar to that of a large window. When reflected or "bounced" off a ceiling, the lighting resembles that of fluorescent tubes. As this very broad, flat lighting is more typical of an overcast day outdoors, a more realistic interior illumination is achieved by reducing the power of additional lighting relative to the available light, so that either source may act as a fill to the other. Hence bounce lighting may provide either the primary or secondary (fill) light source, depending on its intensity.

Outdoor techniques

Walls also make ideal reflectors outdoors, reflecting sunlight
Sunlight
Sunlight, in the broad sense, is the total frequency spectrum of electromagnetic radiation given off by the Sun. On Earth, sunlight is filtered through the Earth's atmosphere, and solar radiation is obvious as daylight when the Sun is above the horizon.When the direct solar radiation is not blocked...

 back upon a subject and reducing shadows (and hence overall contrast) according to the color, size and proximity of the wall. A more readily available alternative is the portable, lightweight, collapsible reflector, commercially available in a range of sizes and colors, or improvised using a sheet of card stock or even a bed sheet. Stands may be erected to retain these reflectors, although it is often much more convenient and practical to have an assistant hold and manipulate them.

See also

  • Lighting
    Lighting
    Lighting or illumination is the deliberate application of light to achieve some practical or aesthetic effect. Lighting includes the use of both artificial light sources such as lamps and light fixtures, as well as natural illumination by capturing daylight...

  • Flash
    Flash (photography)
    A flash is a device used in photography producing a flash of artificial light at a color temperature of about 5500 K to help illuminate a scene. A major purpose of a flash is to illuminate a dark scene. Other uses are capturing quickly moving objects or changing the quality of light...

  • Softbox
  • Striplight
    Striplight
    A striplight is a multi-circuit stage lighting instrument. Striplights are one of the most basic types of lighting fixtures available. They usually consist of row of lamps. A single striplight is usually wired internally into either 3 or 4 circuits. Each internal circuit consists of several...

  • Beauty Dish
    Beauty dish
    A beauty dish is a type of photographic lighting device. A beauty dish uses a parabolic reflector to distribute light towards a focal point. The light created is between that of a direct flash and a softbox, hence giving the image a wrapped, contrasted look, which adds a very dramatic effect....

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