Ostara Specialist Narrowband Oxygen III Filter O-III (1.25″)

Narrowband Oxygen III filter is best for visual observations of planetary and gaseous nebulae, the only way you can see very faint objects like supernovae.

Originally used as light pollution reduction filters, O-III filters darken the night sky, allowing greater contrast in the faint details of distant deep- sky objects.

O-III filters are best used on telescopes with an aperture of 8″ or larger.