Center GND Filter 1.2

Center Graduated Neutral Density Filters – C-GND

Center graduated ND (C-GND) filters are used to control the dynamic range within a scene at the time of capture. In a landscape scene the sky is normally brighter than the foreground and at sunrise / sunset a fairly narrow band of light around the sun is far brighter, so a C-GND filter is inserted in front of the lens and moved to a position where the brighter part of the scene is covered by the C-GND filter and the margin between sky and sun, together with the margin between the sun and foreground is faded using the transition areas of the C-GND filter.  The scene is normally metered for highlight area and shadow area and the difference in stops dictate the strength of filter used.  The use of a C-GND filter avoids the heavy darkening of the sky, normally associated with the use of stronger GND filters in sunrise / sunset scenes – the transition areas are normally soft.