Lunt BF3400S 2" Extension Tube

Lunt BF3400S 2" Extension Tube

Description
The Lunt BF3400S blocking filter is housed in a straight 2" extension tube and is designed to be used exclusively with Lunt Solar Systems' front-mounted H-alpha etalon filters. It blocks all out-of-band light including UV and IR, ensuring full protection during solar observing or imaging.

This model offers a large 34 mm clear aperture and supports telescopes with focal lengths up to 3060 mm. It features a 2" input, a 1.25" eyepiece output, and a T2 thread for direct camera or accessory connection. Its anodized aluminum construction ensures stability and precision in demanding conditions.

This filter is ideal for professionals or observatories needing reliable and modular H-alpha systems. It is not a standalone solar filter and must be integrated into a full Lunt H-alpha configuration.

Technical specifications
• Product reference: 0553013
• EAN: 4007922035871
• Clear aperture: 34 mm
• Tube length: 97 mm
• Outer diameter: 50.8 mm
• Eyepiece connection: 1.25 inch
• Tube connection: 2 inch
• Thread: T2
• Material: Black anodized aluminum
• Compatibility: Telescopes up to 3060 mm focal length

User benefits
• Maximum safety for H-alpha solar observation
• Wide aperture for large focal length systems
• Direct connection to T2-threaded accessories
• Durable and lightweight construction
• Seamless integration into Lunt modular systems

Additional information
• Must only be used with a front-mounted H-alpha etalon from Lunt
• Not a standalone solar filter
• Suitable for visual or imaging applications
• Intended for expert and professional users