Optec Gemini Focusing Rotator

Starting Price: $3,595.00
Price as Configured: $3,595.00

Brand: Optec / SKU: OP-19750

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.

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Product Overview Specifications Included Downloads

Like all Optec focuser products, Gemini includes a remote temperature probe for automatic temperature compensation. Simply attach the temperature probe anywhere in the linear response zone of your OTA (usually the tube or truss assembly) and Gemini will automatically keep the camera package in sharp focus. The Gemini Commander software provides a convenient wizard to help determine your telescope's TC or temperature coefficient.

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.

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, the Gemini package now includes Optec's #19830 OPTEC-4300 to DSI threaded adapter. This part converts the camera side to a receiver for any of Optec's DSI 3.5" spacers configurable to 1/4" increments when additional back-focus spacing is needed.

Currently designed telescope adapters include support for the AG Optical iDKs, Celestron, Ceravolo Optical Systems Astrographs, Meade 16-inch class SCT, PlaneWave Secure-Fit, and Takahashi telescopes.