4 x 5.65" Firecrest ND 2.1 FilterSKU FC4X5ND2.1
The Formatt-Hitech 4 x 5.65" Firecrest ND 2.1 Filter is a solid neutral density filter providing a 7 stop reduction in exposure. This 2.1 density creates a darkening of the entire image, allowing you to photograph with a wider aperture or longer shutter speed than normally required. By slowing your exposure time or increasing your aperture, you are able to control depth of field and convey movement more easily.
The design of this filter has been optimized for use with digital sensors and promote nearly flat attenuation of visible, UV, 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. This filter provides a high level of neutrality across all three spectrums in order to eliminate color casts and ensure cleaner, truer blacks.
Sandwiched between layers of Schott Superwite glass is a 15-layer Firecrest multi-coating, which helps to minimize reflections and flare in order maintain truer colors and contrast. Since the coating is located within the middle of the filter, it is less prone to scratching or damage and results in a more durable and hydrophobic design. This filter measures 4 x 5.65" / 101.6 x 143.5mm and is 0.16" / 4mm-thick.