This 1.3 to 8.7-stop, 82mm Hoya Solas Variable ND Filter is a solid variable neutral density filter that provides an exposure reduction of 1.3 to 8.7 stops. The 0.4 to 2.6 optical density creates a darkening of the entire image, allowing you to photograph with a wider aperture or slower shutter speed without overexposing your image. By slowing your exposure time, you can create motion blur for special effects or to convey a sense of movement. Opening your iris allows you to create shallow depth of field, which can help isolate your subject.
The degree of density is easily controlled by rotating the front filter ring, helping you to predetermine the additional exposure length required. For easier, repeatable control over density settings, the front ring is also visually demarcated with lines that represent different density values.
This Hoya variable neutral density filter is constructed from optical glass for clarity and color fidelity. To prevent internal ghosting and reflections, each glass surface includes 10-layers of anti-reflection coating. These coatings also provide further protection to the filter substrate and helps it to stay clean for longer than with uncoated filters. The design of this filter has also been optimized for use with digital sensors and to promote nearly flat attenuation of visible light and infrared light. Due to imaging sensors' greater susceptibility to infrared light, compared to traditional film, color casts can occur when photographing darker subjects that require increased exposure times.