The Antlia Dualband Solar ERF combines Hydrogen Alpha, Calcium K-Line, and Calcium H-Line into one powerful filter. It protects your solar imaging equipment by rejecting excessive heat before it enters your telescope. This prevents bandpass shifting and ensures safe, stable performance during solar imaging and observation.

Pair this filter with the Antlia Solar Discover 3nm CaK, 5Å CaK, or similar products to keep your gear cool and operating at peak efficiency. It blocks harmful UV and IR light, while allowing the precise wavelengths you need—H-alpha at 656.3nm, CaK at 393.3nm, and CaH at 396.8nm—to pass through.

Key Features:

Hydrogen Alpha Channel:

• FWHM: 25nm centred at 656.3nm (H-alpha)
• Transmission: Greater than 95%

Calcium K & H Channels:

• FWHM: 25nm centred at 393.3nm (CaK)
• Covers both CaK (393.3nm) and CaH (396.8nm)
• Transmission: Greater than 90%

Wide Coating Range:

• Effective across 200-1700nm wavelengths
• Finished with advanced multicoatings for durability and performance
• Coated on heat-resistant, double-polished substrates to maintain optical quality

Mounting Options:

• 130mm, 150mm, and 200mm ERFs come pre-mounted in robust housings, designed to position securely at the front of your telescope
• The 2-inch ERF filter mounts at the rear end of refractor telescopes for easy integration

Precision Optical Quality:

• Transmitted wavefront accuracy rated at λ/4 or better, ensuring minimal distortion in your imaging

The Antlia Dualband Solar ERF gives you maximum protection and optimal performance for solar astrophotography. It keeps your equipment safe, stable, and ready for high-contrast solar imaging sessions.

Spectrum Curve:

Important Notes:

• Always use the Antlia Dual ERF filters with professionally designed solar imaging equipment that includes complete blocking filters. Compatible systems include the Antlia Solar Discover 5Å CaK, Solar Discover 3nm CaK Assembly, and Dualband Ha, CaK, and CaH filter assemblies.

• Never use the Antlia Dualband ERF filter on its own for visual observation.

• The 2-inch ERF filter is only suitable for refractors with apertures of 110mm or smaller.