Lunt blocking filter for H-alpha sun observation B1200 - 2″ angled return

Lunt B1200 blocking filter: Solar observation in H-alpha light

The Lunt B1200 blocking filter, integrated into a 2" angled return, is an essential component for observing the Sun in H-alpha light. Designed to guarantee total safety and exceptional image quality, this filter is optimized to isolate the Hydrogen Alpha spectral line (656.28 nm). With a diameter of 12 mm, it offers an enlarged field of view, ideal for telescopes equipped with 2" eyepiece holders and focal lengths up to 1080 mm. This model is perfect for demanding solar astronomers wishing to combine visual observation with advanced astrophotography.

What is the purpose of a blocking filter?

A blocking filter is one of the key elements of an H-alpha solar system. Whereas the Fabry-Perot standard isolates a narrow band around the H-alpha line, the blocking filter acts as a "spectral cleaner". It eliminates stray wavelengths and unwanted harmonics, ensuring that only light centered on 656.28 nm reaches the eyepiece or camera.

The B1200 model, with its generous 12 mm diameter, is designed for :

• Offer comfortable observation of the complete solar disk.
• Be compatible with medium- to large-sized sensors for imaging.
• Guarantee a sharp, high-contrast image thanks to its multi-layer system.

Key features

• Blocking filter diameter : 12 mm (B1200), optimized for focal lengths up to 1080 mm.
• Integrated angled return : 2" format, compatible with standard 2" or 1.25" eyepieces (adapter included).
• Integrated T2 thread : Allows easy connection to astrophotographic cameras.
• Maximum safety : Complies with international standards for safe solar observation.
• Spectral optimization : Eliminates unwanted harmonics to isolate exclusively the H-alpha line (656.28 nm).
• Robust construction: Machined aluminum case with high-precision optical components.

Why choose the Lunt B1200 blocking filter with 2" angled return?

• Advanced visual observation : The B1200 offers an enlarged field of view, perfect for comfortably observing the complete solar disk with moderate focal length telescopes.
• Advanced astrophotography : Thanks to its 12 mm diameter and integrated T2 thread, it is ideal for capturing detailed images with modern sensors.
• Outstanding image quality : Thanks to its multi-layer system, it guarantees sharp, high-contrast images without light interference.
• Total safety : Effectively blocks harmful UV and IR radiation, ensuring safe use for your eyes and equipment.
• Universal compatibility : Works with all Lunt solar telescopes equipped with a 2" eyepiece holder.

Recommended applications

• Visual observation of the Sun in H-alpha : Explore solar prominences, filaments and chromospheric granulation with optimum contrast.
• Advanced solar astrophotography : Compatible with modern cameras equipped with medium and large sensors.
• Ideal for focal lengths up to 1080 mm, on intermediate or advanced instruments.