M90 to M90 Extension Tube – 50mm

The Dark Clear Skies M90 to M90 50mm Extension Tube is a precision-machined spacer designed to extend optical path length in large-format astrophotography imaging trains.

Featuring M90×1 male threads on both ends, this extension tube is ideal for use with large camera adapters, reducers, flatteners, and filter systems that require accurate back focus spacing. The 50mm optical length allows coarse spacing adjustments while maintaining a rigid and well-aligned imaging train.

Manufactured from high-quality aluminium and internally blackened, the tube minimises reflections and preserves contrast when used in demanding imaging setups.

Key Features

• M90×1 male to M90×1 male threads
• 50mm extension length
• Ideal for large-format astrophotography systems
• Precision-machined aluminium construction
• Internally blackened to reduce reflections

Specifications

• Thread Type: M90 × 1 (male to male)
• Extension Length: 50 mm
• Material: Aluminium alloy
• Application: Astrophotography back focus spacing
• Finish: Black anodised

Typical Applications

• Back focus adjustment for reducers and flatteners
• Large-format camera imaging trains
• Astrophotography spacing solutions
• Rigid optical train extension