Lunt blocking filter for H-alpha sun observation B1800 - 2″ straight tube

Lunt B1800 2” Straight Tube Blocking Filter - Specifications and Features

Visit Lunt B1800 blocking filter, integrated into a 2” format straight tube, is an indispensable component for H-alpha solar observation. Designed to guarantee total safety and exceptional image quality, this filter is optimized to isolate the Hydrogen Alpha spectral line (656.28 nm). With its generous 18 mm diameter, it offers an enlarged field of view, ideal for telescopes equipped with 2” eyepiece holders and focal lengths up to 1620 mm. This model is particularly suited to configurations requiring a reduced optical path, such as advanced solar imaging or use with modern cameras.

What is the purpose of a blocking filter?

A blocking filter is essential in any H-alpha solar system. While 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 B1800 model, with its 18 mm diameter, is designed for :

• Offer comfortable, detailed observation of the complete solar disk.
• Compatible with medium to large sensors for accurate images.
• Maximize optical quality with its multi-layer system.

Key features

• Blocking filter diameter18 mm (B1800), optimized for focal lengths up to 1620 mm.
• Straight tube2” format, ideal for configurations requiring a short optical path.
• Multiple connections :
  • 2" inlet for eyepiece holder.
  • 1.25" outlet with integrated T2 thread for camera or eyepiece.
• Maximum safetyConforms to international standards for safe solar observation.
• Spectral optimizationEliminates unwanted harmonics to isolate only the H-alpha line (656.28 nm).
• Robust constructionAluminium case machined with high-precision optical components.

Why choose the Lunt B1800 blocking filter in straight tube?

1. Advanced visual observation and imagingThe B1800 offers a wider field of view and is ideally suited to medium to large-sized sensors.
2. Compact, versatile designThe straight tube format is ideal for configurations where the optical path needs to be reduced, such as solar astrophotography.
3. Outstanding image qualityThanks to its multi-layer system, it guarantees sharp, high-contrast images without light interference.
4. Total safetyBlocks harmful UV and IR radiation, ensuring safe use for your eyes and equipment.
5. Universal compatibilityWorks with all Lunt solar telescopes fitted with a 2" eyepiece holder.

Recommended applications

• Visual observation of the Sun in H-alphaExplore solar prominences, filaments and chromospheric granulation with optimum contrast.
• Advanced solar astrophotography: Compatible with modern cameras thanks to integrated T2 thread.
• Ideal for focal lengths up to 1620 mmon intermediate or advanced instruments.

Included in the package

• Lunt B1800 blocking filter integrated into a 2” straight tube.
• Adapter for 1.25" eyepieces.
• Detailed user manual.

Compatibility

The B1800 blocking filter is designed for use with :

• Lunt solar telescopes such as the LS80THa or LS100THa.
• Standard 1.25" or 2" eyepieces.
• Modern astrophotographic cameras with T2 threads.

Important

The B1800 blocking filter must be used exclusively with a solar telescope equipped with an H-alpha standard. It cannot be used alone or as an independent accessory on an instrument not dedicated to solar observation.

Transform your solar viewing experience with the Lunt B1800 blocking filter in a 2” straight tube.”. Enjoy a clear, safe view of the Sun in H-alpha light as you explore its fascinating structures!