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 40.5mm Light Red Filter is a basic contrast filter, primarily for use with black and white film, that completely absorbs blue and green tones, enhances reds, and increases contrast for outdoor photography. It also helps to cut through atmospheric haze and is suitable for infrared photography for moon light effect. There is an approximate 8x filter factor with this filter, requiring an increase of 3 stops for normal exposure.