Umbrella reflector

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

Apart from certain highly specialized components found in enlargers, projectors and scanners, photographic reflectors fall into two main groups:

Similar to a domestic lampshade, 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 inner surfaces and directing it towards the scene to be photographed. Although there are a large number of variants, the most common types are:

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.

Also known as plane 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 in both artificial and natural lighting, in place of a fill light 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.

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