The Heliopan 28mm Soft Focus Filter diffuses and softens strong light entering the lens and produces a glowing effect. While the resulting image appears softer and ethereal, there is little loss of clarity or detail. This filter works by diffusing the light entering the lens with small aberrations; by spreading the light more evenly, a soft glow is created rather than the sharp, well-defined image when shooting without a filter. The 0 filter provides a subtle amount of softening. Soft focus lenses for portraiture and landscapes to create a soft, moody effect. In portraiture they also minimize blemishes and the need for retouching. For easiest use focus first without the filter. Best results obtained at largest aperture. At smaller apertures sharpness increases. EXPOSURE FACTOR NONE.