The Hoya 67mm YA3 Pro Orange Filter can be used to increase image contrast when photographing using a film camera system with black-and-white film installed.
This filter's effect corresponds to that of a Wratten 21 filter. Wavelengths of visible light that are apparent as green, blue, and violet colors to the human eye are suppressed, while visible light associated with yellow, orange, and red colors are able to more easily pass though the Hoya 67mm YA3 Pro Orange Filter and into the lens it is mounted in front of. When photographing with this filter along with black-and-white film, green, blue, and violet-colored subjects within a scene are reproduced in dark shades of grey than if a filter was not used. Simultaneously, yellow, orange, and red subjects are rendered in light shades of grey.
When applied to black-and-white photography, the increased contrast provided by the Hoya 67mm YA3 Pro Orange Filter can result in dark skies with very defined clouds. Shades of green among foliage can be much more differentiated relative to skin tones, while the appearance of freckles and skin blemishes is reduced. Additionally, this filter can also minimize the presence of haze caused by the bluish cast of daylight.
To prevent internal ghosting and reflections, each glass surface includes three layers of anti-reflection coating. These coatings also offer greater protection to the filter substrate and help it to stay clean for longer than with uncoated filters. This filter is constructed from optical glass for clarity and features an aluminum-alloy filter ring for durability while remaining lightweight.