Sharpstar 2" 1× Newtonian Coma Corrector (Full Frame, f/3–f/6)

Sharpstar 2" 1× Full-Frame Coma Corrector is a four-element corrector designed for Newtonian reflectors with a parabolic primary mirror. It is optimized to effectively reduce coma in fast optical systems, helping stars remain sharp and round toward the edges of the frame. With a 1× factor, it does not change the telescope focal length, while the standard 55 mm backfocus makes it easy to build an imaging train for DSLR and dedicated astronomy cameras. A 44 mm image circle allows the corrector to be used with full-frame sensors as well.

Key features

• coma corrector for Newtonian telescopes with a parabolic primary mirror
• 1× factor – no focal length or image scale change
• 44 mm image circle, suitable for full-frame sensors
• air-spaced quadruplet design with an ED glass element
• recommended telescope focal ratio range: f/3 to f/6
• standard 55 mm backfocus for convenient DSLR/astro camera setups
• 2" (50.8 mm) barrel for easy installation in a focuser
• full-surface multi-layer coatings on optical elements

Box contents

• Sharpstar 2" 1× coma corrector
• baffle ring

Technical specifications

• application: 150–600 mm paraboloid (parabolic) Newtonian reflectors
• focal ratio: f/3–f/6
• reduction factor: 1.0×
• image circle: 44 mm
• optics: quadruplet (4 elements), air-spaced, includes an ED element
• backfocus: 55 mm (distance from the baffle ring end face to the focal plane)
• outer diameter: 50.8 mm (2")
• overall length: 118.7 mm
• coating: full-surface multi-layer coatings
• weight: 0.35 kg

Sharpstar’s 2" 1× coma corrector is a practical choice for fast Newtonians when you need consistent star shapes across the frame without changing focal length, and want a straightforward 55 mm backfocus for common astrophotography imaging trains.