Lee's Filter Sets include some of the most popular 100 x 100mm (4x4") and 100 x 150mm (4 x 6") resin and glass filters. These filters are designed to work with the versatile LEE Filter Holder System or LEE Slotted Lens Hoods.
Graduated Neutral Density
Often it is necessary or desirable to balance the light intensity in one part of a scene with another. This is especially true in situations where you don't have total light control, as in bright contrasty landscapes. Exposing for the foreground will produce a washed-out, over-exposed sky while exposing for the sky will leave the foreground dark and under-exposed. Lee Grad ND filters are part clear, part neutral density (available in grades of 0.3 (1 stop), 0.6 (2 stops), 0.9 (3 stops)). They allow the transition to be blended into the scene, often imperceptibly. A neutral density 0.6-to-clear, with a two stop differential, will generally compensate the average bright sky-to-foreground situation and is also the most popular density of the series.
81A Warming Filter
The 81 Series of filters controls the bluish coloration that can affect daylight film. They warm scenes shot on cloudy days. They can also remove excessive blue from the effects of electronic flash. These filters are also good for general scenics when the photographer wishes to remove the bluish cast from open shade or just add warmth to the photograph. The 81 series is available in grades from 81 through 81EF, with 81EF having the warmest effect.
81 Series Color Conversion Chart
Light rays which are reflected become polarized. Polarizing filters are used to select which light rays enter your camera lens. They can remove unwanted reflections from non-metallic surfaces such as water or glass and also saturate colors providing better contrast. The effect can be seen through the viewfinder and changed by rotating the filter. The filter factor varies according to how the filter is rotated and its orientation to the sun. Filter factor is between 2.3 and 2.8 (approx. +1.3 stops). Circular polarizers are specifically designed for use with auto-focus SLR cameras (They will also work on manual systems and video cameras without problems).
This filter is glass and measures 4x4".