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Absorptive Neutral Density (ND) Filters used in light control applications for measuring instruments and exposure control in imaging are available at Edmund Optics.
Learn how to use the digital graduated neutral density filter technique in Photoshop to deal with high contrast scenes.
Parts are marked with OD 0.05 but actual optical density on these parts is 0.04 +/- 4%. Features Absorptive Neutral Density Glass for Low Power Applications
NEUTRAL DENSITY FILTERS. Neutral density (ND) filters reduce the amount of light entering the camera, enabling a longer exposure time than otherwise possible.
The Tiffen 77mm Neutral Density 0.9 Filter is a solid ND filter with an 8x filter factor that provides a 3 stop exposure reduction. Its 0.9 density creates a...
Amazon.com : Hoya 52mm Neutral Density ND-400 X, 9 Stop Multi-Coated Glass Filter : Camera Lens Neutral Density Filters : Camera & Photo