Editing Light characteristic (section)

===Occulting light===
[[File:Coquet Island Lighthouse, former occulting mechanism.jpg|thumb|right|upright|250px|Clockwork occulting mechanism formerly in use at [[Coquet Island#Coquet Lighthouse|Coquet Island Lighthouse]].]]
An occulting light is a rhythmic light in which the duration of light in each period is longer than the total duration of darkness. In other words, it is the opposite to a flashing light where the total duration of darkness is longer than the duration of light. It has the appearance of flashing off, rather than flashing on. Like a flashing light, it can be used for a single occulting light that exhibits only a single period of darkness or the periods of darkness can be grouped and repeated at regular intervals (abbreviated "Oc"), a group (Oc(3)) or a composite group (Oc(2+1)).

The term [[occulting]] is used because originally the effect was obtained by a mechanism (e.g. a vertical or rotating shutter) periodically shading the light from view.