The 100 x 100mm K-Series Night Filter from H&Y Filters is designed to reduce the appearance of light pollution in images or video that include the night sky and illumination from artificial light sources. This effect can be obtained when this filter is used on a film camera system with daylight film installed, or on a digital camera system with its daylight white balance setting selected.

Light pollution occurs in areas of the night sky that are above or near concentrated and intense sources of artificial light such as cities. These light sources can include exterior and interior lamps for commercial or residential buildings, brightly lit advertisements such as billboards, streetlamps, as well as sports and entertainment venues. Together, they can result in a type of light pollution known as skyglow, where individual stars, the Milky Way, and other astronomical features in the night sky are obscured. Additionally, artificial lights clustered together can become difficult to individually discern. Light pollution from these "cluttered" sources can become a source of distraction within an image and can resemble overexposed areas of glare.

When used, the 100 x 100mm K-Series Night Filter can improve the results of nighttime images by absorbing the yellow light from sodium-vapor lamps, mercury-vapor lamps, or low Colour Rendering Index LED's, common light sources within urban areas. By preventing the dominant wavelengths of light associated with the colour of those lamps from being recorded, the visibility of astronomical objects is enhanced, and artificial light sources are more clearly defined with less glare and improved contrast.

This 100 x 100mm K-Series Night Filter is constructed from optical glass for clarity as well as colour fidelity. Each side of this filter includes eight layers of anti-reflection coating to prevent internal ghosting and reflections as well as an anti-smear, nano coating for an improved beading effect when in contact with water or oil for greater cleaning efficiency.

The 100 x 100mm K-Series Night Filter is pre-installed with an H&Y Filters 100 x 100mm Quick Release Magnetic Filter Frame for use with an H&Y Filters 100mm K-Series Filter Holder. When combined with a 100mm K-Series Filter Holder that is configured with a pair of magnetic filter slots, filters each with a Quick Release Magnetic Filter Frame can be magnetically stacked in front of a camera lens instead of inserted only within a specific number of filter holder slots, allowing the user to determine the number of filters to be applied, all of which can be quickly installed, repositioned, or switched with a different filter needed for other subjects or changing lighting conditions.

While in use, this Quick Release Magnetic Filter Frame also serves to reinforce the edges of the 100 x 100mm K-Series Night Filter, enhancing that filter's rigidity and promoting sharp results by helping to ensure that the filter remains flat. A filter pouch for storage and transport, as well as a microfiber cleaning cloth for filter maintenance, are also provided.

H&Y Filters 100 x 100mm K-Series Night Filter

Reduces the appearance of light pollution in images or video that include the night sky and illumination from artificial light sources

For cameras with daylight film installed, or a digital camera system with its daylight white balance setting selected

Absorbs the yellow light from sodium-vapor lamps, mercury-vapor lamps, or low Colour Rendering Index LED's, common light sources within urban areas

Enhances the visibility of astronomical objects, and where they appear, artificial light sources are more clearly defined with less glare and improved contrast

2x filter factor reduces exposure by 1 stop

Constructed from optical glass for clarity

Each glass surface includes eight layers of anti-reflection coatings to prevent internal ghosting and reflections as well as an anti-smear, nano coating for an improved beading effect when in contact with water or oil for greater cleaning efficiency

Filter pouch for storage and transport, as well as a microfiber cleaning cloth for filter maintenance

H&Y Filters 100 x 100mm Quick Release Magnetic Filter Frame

Pre-installed along the edges of the included 100 x 100mm K-Series Night Filter for use within an H&Y Filters 100mm K-Series Filter Holder that is configured with a pair of magnetic filter slots

Allows 100 x 100mm K-Series Night Filter to be magnetically stacked in front of a camera lens along with other filters that have a Quick Release Magnetic Filter Frame installed, instead of inserted only within one of a specific number of filter holder slots

Helps allow the user to determine the number of filters to be applied when using a 100mm K-Series Filter Holder, all of which can be quickly installed, repositioned, or switched with a different filter needed for other subjects or changing lighting conditions

Reinforces the edges of the 100 x 100mm K-Series Night Filter, enhancing that filter's rigidity and promoting sharp results by helping to ensure that the filter remains flat

Front-facing centre finder rulers on side sections of this Quick Release Magnetic Filter Frame help enable precise positioning of the 100 x 100mm filter it is installed on, relative to another filter that 100 x 100mm is stacked on.