Baader M68 Extension Tube – 10 mm

Baader M68 Extension Tube – 10 mm

Description
The Baader Planetarium M68 – 10 mm extension tube is engineered for optical setups requiring precise backfocus adjustment and maximum mechanical stability. In astrophotography and spectroscopy, even a minimal amount of flexure or tilt between the telescope and the camera can cause loss of sharpness, apparent miscollimation, or optical distortion.

This issue is particularly critical when using long, heavy accessories such as telecentric systems or the Fluorite Flatfield Converter (FFC), which exert significant leverage on the focuser. Slip-fit connections, even those with brass compression rings, cannot always eliminate such micro-shifts entirely.

The M68 x 1 thread, a standard used in high-end instruments like Zeiss telescopes, provides a large and stable screw connection that eliminates play and tilt. Made from high-quality precision-machined aluminium, this extension tube offers a perfect fit, wide contact surface, and uncompromising stability.

With its 10 mm optical path, this extension is ideal for:

• Fine-tuning backfocus in imaging or spectroscopy setups

• Achieving optimal working distance when using an FFC for planetary imaging

• Operating telecentric systems with H-alpha filters for high-resolution solar observation

• Ensuring mechanical and optical compatibility with M68 and Zeiss accessories

The interior is carefully blackened to suppress stray light and maintain image contrast, even under bright-light conditions. Precision threading ensures smooth assembly, no binding, and perfect concentricity with the optical axis.

This extension tube can be used alone or combined with other M68 extensions to reach the desired length. It integrates seamlessly into Baader’s modular M68 system, providing compatibility with a wide range of accessories and adapters to other standards, such as Astro Physics 2.7", M60 Vixen, or M56 Synta.

Technical specifications

• Manufacturer: Baader Planetarium

• SKU: 2458201

• EAN code: 4047825009975

• Adapter family: M68 system

• Optical length: 10 mm

• Telescope-side external thread: M68 x 1

• Accessory-side internal thread: M68 x 1

• Clear aperture: 62 mm

• Outer diameter: 76 mm

• Weight: 0.03 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