Cokin

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.

Cokin produce various differently-sized versions of the Creative Filter System.

The "A" and "P" sizes in particular are de facto standards, with many other manufacturers producing compatible filters and holders.

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