Antlia Solar Discover Dualband Ha, CaK and CaH Filter Assembly
The Antlia Solar Discover Dualband filter (Ha, CaK and CaH) is specially designed for solar imaging of the photosphere. It enhances contrast and sharpness, making it possible to better reveal solar surface details such as sunspots and solar faculae. The system incorporates an Energy Rejection Filter (ERF) that blocks UV and IR, while allowing only Ha (656.3nm), CaK (393.3nm) and CaH (396.8nm) wavelengths to pass through.

Key features
- Selective filtration of Hα, CaK and CaH bands
- Closed tubular structure in CNC aeronautical aluminum, strong and durable
- Light-tight assembly, with no parasitic light leaks
- Integrated ND filter for sunlight reduction
- Superior resolution and contrast compared with conventional solar films
- Ease of use and extended system life
- Available in Standard (1.25″ + 2″) and Mini (1.25″) versions
Compatibility
- Adapters included: 1.25″ and 2″ for the Standard version; 1.25″ for the Mini version
- Fast connection to telescopes and astrophotography cameras
- Compatible with refractors up to 100mm aperture without additional reduction
Important notes
- If used with a zenithal mirror, the ERF must be positioned correctly.
- For telescopes over 100mm in diameter, use of an additional light reduction filter (ERF, solar film, diaphragm) is mandatory.
- Without additional reduction, use reserved for ≤100mm refractors.
About visual observation
The Solar Discover Dualband Ha, CaK and CaH is not recommended for visual observation. IR coverage differs slightly from the ISO 12312-2 standard for sunglasses. For any attempt at visual observation, it is imperative to check that all filters are intact and in perfect working order.
Compliance with transmission standards
- Tmax% (380-780nm): 0.0032%
- Tmin% (380-780nm): 0.000061%
- Tmax% UVB (280-315nm): 0.0032%
- Tmax% UVA (315-380nm): 0.0032%
- Tmax% IR (780-1700nm): 3%
Version (make sure you order the right one)
- Standard version
- Mini version
Warranty
- 3-year manufacturer's warranty
- Any disassembly of the assembly voids the warranty.
- No returns, exchanges or repairs accepted after disassembly