Gemini Focusing Rotator
Gemini Focusing Rotator
Gemini Focusing Rotator
Gemini Focusing Rotator


Gemini Focusing Rotator

Regular price
$ 3,595.00
Sale price
$ 3,595.00
Unit price

This item is out of stock but you can place an order now and we’ll ship when it becomes available.


Low-Profile Focusing Rotator System

Optec engineers have developed a completely new concept for combining telescope focus and camera rotation functions into a single robust, yet compact package.  Rather than simply adding a rotator onto the end of a focuser drawtube, Gemini was designed from inception with a rotating drawtube providing superior strength and rigidity for heavy camera payloads.  Featuring four lead-screws and four linear bearings, Gemini can easily handle 10-kg. (22-lbs.) payload packages without flexure.  Full 360-degree rotation is a built-in function of the Gemini with a full 1/2" of linear travel.  At the center of travel, Gemini measures a mere 2.45" in thickness. 

Robust Compact Design

 To maintain a flat, rigid base for heavy camera packages, Gemini's shell consists of two parallel plates machined from MIC-6 tool plate providing flatness within 0.001" (25 microns).  Seven precise stand-off spacers maintain the 2.2" separation of these plates.  The rotating drawtube is moved linearly with 1/2" of total travel using a premium timing belt driven by a high torque stepper motor.  The entire package is accented with a beautiful carbon fiber wrap.  Dual RJ45 connectors provide connection to the Gemini Control hub.  The independent rotating drawtube is supported by a custom X-cage bearing system supported by large, 6mm chrome ball bearings.

Support for Multiple Telescopes

Featuring identical OPTEC-4300 mechanical interfaces front and back, the Gemini can be easily fitted to most any large telescope OTA.  Recessed oval point setscrews provide three-point direct contact with the heavy wall OPTEC-4300 dovetail mount.  Gemini's clear aperture of 3.75" is maintained through each adapter, passing even large light cones through to the camera image plane without vignetting.

On the camera side, a typical configuration might include a 4300 receiver for the Optec-DSI 3.5 High Performance spacer sets configurable to 1/4" increments when additional spacing is needed. 

Currently designed telescope adapters include support for the AG Optical iDK's, Ceravolo Optical Systems Astrographs, Meade and Celestron 10-inch and larger class SCT, and Plane Wave Secure-Fit. 


 Gemini 96 FocusingRotator

Gemini Focusing Rotator provides both focus and rotation in a single device. Wide 3.75” opening designed for very large payload systems with limited back-focus. Overall thickness is 2.25” with ½” of focuser travel. Package includes Gemini controller, Hand Controller, power supply, cables and Pelican type case. Order OPTEC-4300 adapters for telescope and camera side connections. Stock item #19830 OPTEC-4300 to DSI 3.5x24tpi threaded adapter is now included for the camera side mount.See Optec-DSI 3.5x24tpi threaded extension section for spacer selections.[OPTEC-4300 female dovetail // OPTEC-4300 female dovetail (includes DSI 3.5 female adapter)]


Gemini 120 Big-Bore Focusing Rotator

Special variant of the Gemini Focusing Rotator with large 120mm opening. Re-designed thrust bearing allows even more light throughputand heavier loads than the original Gemini 96mm Focusing Rotator


Note: OPTEC-4300 Dovetail Mounts required for both Telescope and Camera Side Interface - Sold Separately 

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