Sightron - Dual BP Filter Ø 31.7 mm

Dual BP Filter Ø 31.7 mm (1.25")

The Sightron Dual BP Filter (Dual Bandpass Filter) primarily transmits wavelengths near the two main emission lines (Hα, OIII) emitted by celestial objects and cuts off other wavelengths, allowing nebulae to appear even in light-polluted areas.
It is ideal for photographing nebulae in urban areas using digital SLR and mirrorless cameras.

Product Features

Type with two emission lines

By primarily transmitting in the wavelength regions around the two main emission lines (Hα and OIII) emitted by celestial objects and cutting off other wavelength regions, comets and nebulae can appear even in light-polluted areas. In particular, the emission lines of OIII at 495.6 nm and 500.7 nm are transmitted to enhance the image of OIII.

Reliable quality from Japan

Synthetic quartz glass is used as the substrate. It is stronger and more heat-resistant than the optical glass normally used, so distortion during coating is even lower than usual, and the stability and precision of the coating surface are excellent. The filter prevents image degradation even when photographing planets at high magnification. Made in Japan by a major Japanese optical equipment manufacturer.

Universal thread diameter 31.7 mm (1.25")

Standard diameter of Ø 31.7 mm that can be used with many telescopes.