Tiffen Color & Nuetral Density (ND) Grad filters are one of the most widely used category of filters in the industry today. They enable the image-maker to create an illusion or enhance reality. Some of the most popular applications are: * Adding color excitement to a drab sky * Changing the specific color in a scene to create a desired special effect * Enhancing the existing color or creating subtle color drama * Creating more balanced exposure in uneven lighting situations Tiffen Color & ND-Grads are supplied in a wide range of sizes and colors and are made in either soft edge, (Depending on the size of the filter, the transition area is between 1/2" to 2" wide before reaching full density) hard edge, (Depending on the size of the filter, the transition area is approximately 1/4" to 1/2" wide before reaching full density) or as a special order, attenuated gradients. (The transition area takes place throughout the whole filter, starting clear and reaching its maximum density at the opposite end) When it comes to rectangular-shaped filters, such as the 4x5.650 (Panavision size), the terms vertical and horizontal are important ( The horizontal or vertical designation refers to the position of the filter in relationship to the camera when the grad line is horizontal) Hard Edge - Soft Edge In addition to subject matter and its surroundings, the type of lens you use will help to determine whether to use a T