Starfield Optics 2" Richey-Chretien R&P focuser . EAF Compatable

2" Linear-Bearing Crayford Focuser (ZWO EAF Mount-Ready) for 6" & 8" GSO RC/CC

If you’re upgrading the stock focuser on a GSO 6" or 8" Ritchey-Chrétien (or Classical Cassegrain) and you want smoother motion, better load handling, and straightforward motor-focuser mounting, this dual-speed linear-bearing Crayford is built for exactly that. It combines a rigid rail-guided drawtube with fine 10:1 control—great for heavy eyepieces or imaging trains where repeatable focus matters.

What makes it different

Rail-guided stability (less tilt, less “wiggle”)
Instead of relying only on the typical small roller contact points found in many Crayfords, this design uses a stainless linear-rail system that keeps the drawtube supported across its travel for improved rigidity—especially helpful when the scope is aimed low and the imaging payload is working the focuser hardest.

Dual-speed control for critical focus
You get a standard coarse knob plus a 10:1 microfocus for tiny adjustments when stars are almost “there” but not quite. There’s also a drawtube lock for holding focus once you’ve nailed it, and tension adjustment to match the weight you’re carrying.

ZWO EAF-friendly housing (no custom bracket required)
This version is designed with a flat mounting surface and extra mounting points so a ZWO EAF can be attached using the standard bracket that comes with the EAF—no third-party printed adapters needed. (EAF not included.)

Rotation for comfortable framing/observing
Loosen the rotation collar, turn the focuser to a better angle for viewing or camera framing, then lock it back down.

Telescope fitment

• Threads directly onto compatible GSO-manufactured (Astro-tech, iOptron, Orion, etc...) 6" and 8" RC telescopes using the M90x1 female thread on the telescope side.  

• Often found under multiple brand labels (the underlying GSO rear-thread standard is the key).

In the box / features

• 2" eyepiece barrel with brass compression ring

• 2" to 1.25" adapter (with brass ring) and 2" filter threads on the adapter

• Laser-marked drawtube scale for repeatable positioning

• Packaged in a foam-fitted padded box; no printed manual

Focus travel note (important for eyepieces/accessories)

Crayford units are often shorter than some rack-and-pinion focusers. That usually helps with gaining in-focus (nice for imaging/binoviewers), but if you run out of out-focus with certain eyepieces/accessories, the common fix is adding a 2" extension tube.