• The UltraBlock is the filter for deep-sky observers located at highly light-polluted sites
• It blocks all forms of light pollution - mercury vapor and sodium emission bands - while passing the critical hydrogen-beta and ionized oxygen wavelengths
• UltraBlock also enhances the sky presence of a significant number of fainter deep-sky objects over unfiltered and wideband-filtered views
• Available in 1.25" and 2"and as a thread-on for rear cells of Schmidt-Cassegrains

Included Items: