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More products from the brand :Lunt

Lunt blocking filter for H-alpha sun observation B3400 - 2″ straight tube

CHF 3'499

Reference FILB-0012

Disponible en stock chez le fournisseur

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Lunt B3400 2” Straight Tube Blocking Filter - Specifications and Features

Visit Lunt B3400 blocking filter, integrated into a 2” format straight tube, is an essential component for solar observation and imaging in H-alpha light. This filter is designed to guarantee absolute safety and exceptional image quality, optimized to isolate the Hydrogen Alpha spectral line (656.28 nm). With its generous 34 mm diameter, it is ideal for telescopes with focal lengths of up to 3060 mm for visual observation and 1800 mm for imaging. This model is particularly suited to configurations requiring a reduced optical path, such as advanced solar imaging with large-format sensors.

What is the purpose of a blocking filter?

A blocking filter is indispensable in any 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 B3400 model, with its 34 mm diameter, is designed for :

  • Offer an ultra-wide field of view suitable for large-focal length telescopes.
  • Be compatible with large-format sensors to capture detailed images.
  • Maximize optical quality with its multi-layer system.

Key features

  • Blocking filter diameter 34 mm (B3400), optimized for focal lengths up to 3060 mm for visuals and 1800 mm for imaging.
  • Straight tube 2” 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 safety Conforms to international standards for safe solar observation.
  • Spectral optimization Eliminates unwanted harmonics to isolate only the H-alpha line (656.28 nm).
  • Robust construction Aluminium case machined with high-precision optical components.

Why choose the Lunt B3400 blocking filter in straight tube?

  1. Advanced visual observation The B3400 offers an ultra-wide field of view and optimum contrast, perfect for comfortably observing the entire solar disk with long-focal-length telescopes.
  2. Professional astrophotography Thanks to its generous 34 mm diameter and integrated T2 thread, it is ideal for capturing detailed images with modern large-format sensors.
  3. Outstanding image quality Thanks to its multi-layer system, it guarantees sharp, high-contrast images without light interference.
  4. Total safety Blocks harmful UV and IR radiation, ensuring safe use for your eyes and equipment.
  5. Universal compatibility Works with all Lunt solar telescopes fitted 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 large-format sensors, thanks to integrated T2 thread.
  • Ideal for focal lengths up to 3060 mmon intermediate or advanced instruments.

Included in the package

  • Lunt B3400 blocking filter integrated into a 2” straight tube.
  • Adapter for 1.25" eyepieces.
  • Detailed user manual.

Compatibility

The B3400 blocking filter is designed for use with :

  • Lunt solar telescopes such as the LS100THa or LS130THa.
  • Standard 1.25" or 2" eyepieces.
  • Modern astrophotographic cameras with T2 threads.

Important

The B3400 blocking filter must be used exclusively with a telescope or H-alpha system fitted with a Fabry-Perot Lunt Solar Systems standard. It cannot be used alone or as an independent accessory on an instrument not dedicated to solar observation.

Transform your solar observing experience with the Lunt B3400 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!

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