- Carries both round and square filters as well as modular accessories
- Notches found on the filter holder enable rotation of round filters
- Square filters slide within filter-holder slots
The coupling ring enables you to attach a filter holder allowing you to use more than three a second filter-holder, thereby increasing the number of filters used. The coupling ring slides into the Filter- Holder's outer slots. It is particularly useful for orientating square filters in different directions (graduated, multi-images filters etc...).
Cokin filters were invented by professional photographer Jean Coquin. By using square filters like Cokin's, which fit into a holder and are attached to a lens via an adapter ring, the photographer has a number of immediate advantages. There is no need to duplicate filters to fit different size lenses, up to three filters can be used at once to create unique effects, and the photographer has control over the positioning of the effect on the photograph.