40mm f/3.5 ED Guide Scope with Dovetail

The Dark Clear Skies 40mm f/3.5 ED Guide Scope is a high-performance autoguiding solution designed for precision astrophotography. Featuring an ED optical design and lightweight carbon tube, it delivers sharp, well-corrected guide stars even when used with modern small-pixel guide cameras.

With a 40mm aperture and 132mm focal length, this guide scope provides a bright, wide field ideal for accurate tracking corrections on deep-sky imaging rigs. The triplet (2+1) optical construction ensures excellent star shape and minimal aberration across the image circle.

The scope includes a robust dovetail base for finder shoes, a smooth helical focuser with locking ring, and both T2 (M42x0.75) and 1.25" camera connection options, making it compatible with a wide range of guide cameras and mounts.

Key Features

• 40mm ED objective for sharp guide stars
• Fast f/3.5 focal ratio
• Carbon fibre tube construction
• Helical focuser with locking ring
• Dovetail base for finder shoe mounting
• T2 (M42x0.75) and 1.25" camera connections

Specifications

• Aperture: 40 mm
• Focal Length: 132 mm
• Focal Ratio: f/3.5
• Optical Design: Triplet (2+1)
• Image Circle: Up to 1/2.7" sensors
• Tube Material: Carbon fibre
• Overall Length: 154 mm (166 mm with extension)
• Focuser Travel: 15 mm
• Thread: M42 × 0.75 (T2)
• Weight: 389 g (net)

What’s Included

• 40mm ED Guide Scope
• Bracket with dovetail bar for finder shoes
• T2 to 1.25" adapter
• 10 mm T2 extension ring
• Dust caps
• Protective plastic case