Single coatings on both the front and rear offer protection to the glass and help to improve light transmission and image quality.
Constructed from Schott glass for optical clarity.
Brass filter ring helps to prevent jamming and provides additional strength.
The Heliopan Rollei Bay III IR RG 665 is used for infrared photography with digital cameras and specialized infrared film. This nearly opaque filter blocks all visible light up to 665nm, enabling recording of subject matter and scenes that are not visible under normal conditions. Due to the nature of infrared photography, the filter factor for this filter is highly variable and depends largely on the ISO sensitivity in use and lighting conditions.