100mm are professional photography filters for digital and analog photos. They are compatible with conventional filter holders of other brands (such as "P" type 84-85mm width). These filters are made from organic glass, which have first class optical and mechanical properties. Even in area of digital photography, optical square filters are unique in that most of them can not be digitally emulated, (for example gradual ND - Neutral density filter)
Are filters designed to reduce exposure of the upper (darkened) part of the filter, used to reduce highlights/overexposure of the upper part of image / sky.
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Complete system of accessories (holders, rings, sunshades) for almost all cameras and lenses