Cokin is a French manufacturer of

optical filter An optical filter is a device that selectively transmits light of different wavelengths, usually implemented as a glass plane or plastic device in the optical path, which are either dyed in the bulk or have interference coatings. The optic ...

s for

photography Photography is the visual arts, art, application, and practice of creating images by recording light, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is empl ...

. The system allows filters such as rectangular graduated neutral density filters which are versatile in use.

History

Cokin are particularly noted for their "Creative Filter System". It was invented by photographer Jean Coquin and introduced in 1978. Based primarily around square filters, these require a holder which is attached to the lens via a simple adapter ring of the appropriate size. Unlike screw-thread circular filters, which are each tied to lenses of a specific diameter, those in the system can be used with any lens, provided they are large enough to cover it sufficiently. (Only the adapter ring may need changing).

Production

The system includes a wide range of filters including

color correction Color correction is a process used in stage lighting, photography, television, cinematography, and other disciplines, which uses color gels, or filters, to alter the overall color of the light. Typically the light color is measured on a scale k ...

, plain and coloured graduated filters, diffraction,

diffusion Diffusion is the net movement of anything (for example, atoms, ions, molecules, energy) generally from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gradient in Gibbs free energy or chemical p ...

and

polarizers A polarizer or polariser is an optical filter that lets light waves of a specific polarization pass through while blocking light waves of other polarizations. It can filter a beam of light of undefined or mixed polarization into a beam of wel ...

. The material is a polymer, CR-39 sometimes advertised as "organic glass". Cokin produce various differently-sized versions of the Creative Filter System. The smallest is "A" ("Amateur", 67mm wide). The larger "P" ("Professional", 84mm wide) system covers cases where "A" filters are too small to cover the lens (or would cause problems at wider angles). The still-larger "X-Pro" filters are 130mm wide. The "A" and "P" sizes in particular are de facto standards, with many other manufacturers producing compatible filters and holders. Cokin also produce a system for 100mm-wide filters which they refer to as "Z-Pro". "X-Pro" and "Z-Pro" are designed for larger cameras.

References

External links

Cokin UK website
Optical filters French companies established in 1978 Photography equipment manufacturers of France French brands {{France-company-stub