Square & Rectangular Filter Systems
This system also consists of various types and sizes of filters. The most popular sizes are 3x3, 4x4 or 4x6 inch models. These square filters generally weigh less than round glass versions and can also give your photos different types of effects. The system consists of three parts: an adaptor ring for your lenses, a filter holder that fits in to the adaptor and the filters. These filters are generally made of glass or plastic, but some are made of a high quality resin or polyester. One square or rectangular filter can usually fit onto various sized lenses. They often fit onto them with adapter rings. Some of these filters are available with soft or hard transitions from dark to clear. A soft edge is good for wide angle lenses and a hard edge is good for normal and longer sized lenses. The filters range anywhere from about $10 to about $100.