Baader M68 Extension Tube – 60 mm

Baader M68 Extension Tube – 60 mm

Description

The Baader Planetarium M68 – 60 mm extension tube is a critical component for any professional optical setup requiring precise backfocus adjustment. In high-resolution astrophotography or spectroscopy, mechanical stability is essential. Even minimal flexure or tilt in the optical train can lead to focus shift, loss of sharpness, or a significant reduction in data quality.

This issue is particularly critical when using long, heavy accessories such as telecentric systems or the Fluorite Flatfield Converter (FFC). These components apply considerable leverage to the focuser, and slip-fit connections, even with brass compression rings, cannot always guarantee perfect alignment.

By using an M68 x 1 thread, derived from high-end Zeiss telescope standards, this extension tube ensures a wide and robust screw coupling that eliminates play and tilt while maintaining perfect concentricity. Precision-machined from high-grade aluminium, it offers optimal mechanical rigidity and a generous contact surface for secure accessory mounting.

With its 60 mm optical length, this extension is ideal for:

• Precisely adjusting backfocus in complex optical trains

• Achieving optimal working distance with an FFC for high-magnification planetary imaging

• Using a telecentric system with H-alpha filters for solar observation

• Ensuring full compatibility with all M68 and Zeiss standard accessories

The interior is carefully blackened to suppress stray light and maintain maximum image contrast. Precision threading allows smooth, secure assembly without binding, preserving perfect optical axis alignment.

This extension can be used alone or combined with other M68 tubes to achieve the desired spacing. It integrates seamlessly into Baader’s modular M68 system, with optional adapters available for other standards such as 2.7" Astro Physics, M60 Vixen, and M56 Synta.

Technical specifications

• Manufacturer: Baader Planetarium

• SKU: 2458206

• EAN code: 4047825009944

• Adapter family: M68 system

• Optical length: 60 mm

• Telescope-side external thread: M68 x 1

• Accessory-side internal thread: M68 x 1

• Clear aperture: 62 mm

• Outer diameter: 76 mm

• Weight: 0.11 kg

• Material: precision-machined aluminium

• Internal finish: matte black anti-reflective coating

• Usage: extension for eyepiece projection or FFC

• Compatibility: Baader M68 and Zeiss systems