Explore Scientific 3″ Self‑Centering Focuser w/ Back‑Cell Adapter for ED127 / FCD100 Refractors (ES‑FOC3‑BC100127T)

A Serious Focuser for Large Refractors and Heavy Imaging Rigs

If you're running a large refractor like the Explore Scientific ED127 or FCD100 series with a camera, filter wheel, or heavy eyepiece, a standard focuser often isn't up to the job — it sags, tilts, or slips under the weight. The Explore Scientific 3″ Self‑Centering Focuser w/ Back‑Cell Adapter for ED127 / FCD100 Refractors ES-FOC3-BC100127T solves that with a self-centering compression system that locks accessories firmly in place, and a 9:1 micro-focus knob that lets you dial in focus with precision even under load.

The included back-cell adapter mounts directly to compatible Explore Scientific white-tube refractors with no modification required.

Who This Is For

• Astrophotographers running heavy imaging trains (cameras, filter wheels, diagonals)
• Visual observers using large 3" eyepieces on ED127 or FCD100 series telescopes
• Anyone upgrading from a stock focuser that flexes or slips under weight

Key Features

• Self-centering compression system prevents tilt and image shift under heavy loads
• 3" (76.2mm) draw tube handles large eyepieces and full imaging trains
• 84.5mm of travel accommodates thick cameras and accessories
• 9:1 micro-focus reduction for smooth, backlash-free fine focusing
• 17 lb load capacity — handles virtually any imaging setup
• Accepts 2" and 3" accessories via included twist-lock/compression adapters
• Back-cell adapter included for tool-free mounting on compatible scopes
• Black anodized aluminum construction for long-term durability

What's Included

• 3" Self-Centering Focuser (ES-FOC3-BC100127T)
• Back-cell adapter for ED127 / FCD100 / compatible white-tube refractors
• 2" and 3" twist-lock / compression ring adapters
• Internal light-baffle draw tube and mounting hardware

Specs