The Tokina 4 x 4" PRO IRND 1.5 Filter is compatible with filter holders that can accommodate filters that are 4" wide and 4mm thick. It is an ND filter with a 32x filter factor that provides a 5-stop exposure reduction. This filter's 1.5 density creates a darkening of the entire image, allowing you to photograph with a wider aperture or slower 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. Neutral density filters are intended to not affect the coloration of the image and are ideal for pairing with other filters.
The design of this filter has been optimized for use with digital sensors and to promote nearly flat attenuation of visible 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. To provide a high level of neutrality across the visible and infrared spectrums in order to eliminate color casts and ensure cleaner, truer blacks when using this filter, one ACCU-ND Vapor Deposition layer is sandwiched between two layers of optical glass.
This Tokina 4 x 4" PRO IRND 1.5 Filter is constructed from optical glass for clarity as well as color fidelity, and its sandwich design protects the ACCU-ND substrate while the glass surfaces can be re-polished should they become accidentally scratched.