Astronomik Filters H-beta SC filter (43791)

One of the greatest challenges in exploring the night sky is the brightening caused by artificial lights, such as streetlights, which significantly reduce the visibility of celestial objects beyond the Solar System. Near towns or cities, the night sky is far from truly dark, making deep-sky observation difficult. This H-beta filter addresses this issue by dramatically increasing contrast through blocking unwanted artificial light. It leverages a unique property of emission nebulae, which emit light in specific colors known as emission lines. These lines correspond to chemical elements—in this case, hydrogen.

The H-beta filter blocks all other colors, allowing only the hydrogen emission line to pass through. The results are remarkable: nebulae that were previously invisible under light-polluted skies become clearly visible. For example, under suburban skies, the Horsehead Nebula is nearly impossible to see with a 300mm telescope. With this filter, however, the nebula and its intricate structures are revealed effortlessly. It is an essential tool for any visual observer looking to explore faint nebulae.

Specifications

• Capacity:
  • Coating of optical system: Multiple
  • Mount material: Aluminium
  • Half-value width (nm): 12
  • Frame: SC thread
• General:
  • Series: H-beta
  • Type: Filters
  • Type of build: Line filter

Area of Application

• Useful for photographs: Yes
• Visually useful: Yes
• Anti light-pollution: Yes