Formatt Graduated Neutral Density HD Filters enable the shooter to adjust exposure without affecting color balance. Exposure can be increased by 1, 2, 3 or 4 stops to suit individual situations.
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. This filter enables cloud detail to be kept correctly exposed in the picture.
Soft/hard indicates the degree of transition.
- A standard set of ND's is 0.3, 0.6, 0.9 and 1.2. This represents 1 to 4 stops of light reduction 1
Neutral Density Filters Have Four Main Uses
- To enable slow shutter speeds to be used, especially with high speed films, to record movement in subjects such as waterfalls, clouds, or cars
- To decrease depth of field by allowing wider apertures to be used, which helps separate subjects from their background
- To decrease the effective ISO of high speed film (above ISO 400) and allow it to be used outdoors in bright situations
- To allow cine and video cameras (which have fixed shutter speeds) to film subjects such as snow, sand or other bright scenes which could cause overexposure
Neutral Density Factors
- ND.3 (exposure adjustment = 1 stop, reduces ISO 1/2)
- ND.6 (exposure adjustment = 2 stops, reduces ISO 1/4)
- ND.9 (exposure adjustment = 3 stops, reduces ISO 1/8)
- ND1.2 (exposure adjustment = 4 stops, reduces ISO 1/16)
Formatt Grads are Available in Four Types
- Soft Edge - Half clear, half colored with a smooth transition to full density. Generally used with medium to wide angle lenses
- Hard Edge - Half clear, half colored with a definite less subtle transition. For use with long focal length lenses
- Razor Edge - As hard edge but with a solid transition line for shooting corners of buildings, knife-edge horizons or when a very bold transition is required
- Blender - The grad line is right at one edge of the filter so the color change runs from top to bottom. Perfect for irregular objects and skylines