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Optec Gemini Focusing Rotator

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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OP-19691 - Optec Universal Mounting Bracket for Focus Lynx Control Hub
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OP-19691 - Optec Universal Mounting Bracket for Focus Lynx Control Hub
About This Product

The Optec Universal Mounting Bracket screws directly to the back of the FocusLynx Control Hub back and allows easy attachment to most any mount. 

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About This Product
WiFi board with 802.11b/g connectivity to local wireless networks. Works with both FocusLynx and Gemini control boards.

Compatible with:
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About This Product
The 3600 to 4300 Expansion Ring allows owners of any OPTEC-3600 telescope adapter to easily expand the male dovetail out to 4.3-inches matching the OPTEC-4300 spec.

Inside Diameter: 3.6" (91mm)
Outside Diameter: 4.95" (126mm)
Overall Height: 0.42" (10.7mm)
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Weight: 3.4 oz (100 g)
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Camera-Side:
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OP-19839 - Optec-4300 Extension Adapter, 25mm Length
About This Product
The OPTEC-4300 25mm Extension Ring provides approximately 1-inch of extension for any OPTEC-4300 telescope adapter. Ideal for telescopes where the Gemini Focusing Rotator may need to pushed out and away from the OTA to provide clearance for cooling fans or when a little extension is required to reach optimal focus.

Inside Diameter: 3.9" (99mm)
Outside Diameter: 4.95" (126mm)
Overall Height: 1.30" (33.2mm)
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OP-19830 - Optec-4300 to Female Optec DSI 3.5"
About This Product
The #19830 OPTEC-4300 to female Optec/DSI 3.5" threaded receiver allows any combination of our DSI 3.5-inch spacers to be easily installed on the camera side of the Gemini Focusing Rotator.

Inside Diameter: 3.5" DSI Thread
Outside Diameter: 4.95" (125.7mm)
Overall Height: 0.42" (10.7mm)
Clear Aperture: 3.46" (88mm)
Weight: 3.8 oz (110 g)
Back-Focus Usage: 0.1" (2.5mm)

Compatible with:
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OP-19846 - Optec-4300 to Internal 3" Clamp
OP-19846 - Optec-4300 to Internal 3" Clamp
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OP-19846 - Optec-4300 to Internal 3" Clamp
About This Product
OPTEC-4300 to internal 3-inch clamp to allowstight fit of Paracorr, Wynne Correctors, and other 3-inch optics for the Gemini Focusing Rotator. Adjustable placement of lens inside Gemini drawtube allows ideal spacing of corrector / flattener optics to primary mirror. OPTEC-4300 to internal 3-inch clamp to allow tight fit of Paracorr, Wynne Correctors, and other 3-inch optics. Adjustable placement of lens inside Gemini drawtube.

Includes:
3-inch internal clamp assembly with OPTEC-4300 dovetail,
9/64” ball driver,
5/64” hex key.

OP-19831 - Optec-4300 to Male Optec-DSI 3.5" x 24tpi
OP-19831 - Optec-4300 to Male Optec-DSI 3.5" x 24tpi
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OP-19831 - Optec-4300 to Male Optec-DSI 3.5" x 24tpi
About This Product
The #19831 Male Optec/DSI 3.5" to OPTEC-4300 male dovetail fits the telescope side receiver of the Gemini and allows any combination of our DSI 3.5-inch spacers to be easily installed on the telescope side of the Focusing Rotator.

Inside Diameter: 3.165" (80.4mm)
Outside Diameter: 4.95" (125.7mm)
Overall Height: 0.83" (21.0mm)
Clear Aperture: 3.165" (80.4mm)
Weight: 4.8 oz (135 g)
Back-Focus Usage: 0.1" (2.5mm)

Compatible with:
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OP-19843 - Optec-4300 to Takahashi Epsilon 180
OP-19843 - Optec-4300 to Takahashi Epsilon 180
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OP-19843 - Optec-4300 to Takahashi Epsilon 180
About This Product
The #19843 adapter replaces the Captain's Wheel focuser of Takahashi's Epsilon Astrographs and allows attachment of the Optec Gemini Focusing-Rotator.

Optec now offers a complete focusing rotator option for owners of Takahashi's legendary Epsilon 180 Astrograph. Gemini's Low-Profile Focusing Rotator, coupled with the #19843 and #19844 adapters provides a drop-in replacement for the native E180 focuser.

Inside Diameter: 3.90" (99mm)
Outside Diameter: 4.80" (122mm)
Overall Height: .64" (16.2mm)
Clear Aperture: 3.90" (99mm)
Weight: 3.6 oz (100 g)
Back-Focus Usage: 0.25" (6.35mm)
Telescope Side Connection: M108 Takahashi female thread
Camera Side Connection: OPTEC-4300 male dovetail

Telescope Compatibility:
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Device Compatibility:
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TCF-Lynx3 Gen2 focuser (mfg. after Jan. 2018),
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OP-19844 - Optec-4300 to Takahashi Epsilon 180 Field Flattener
OP-19844 - Optec-4300 to Takahashi Epsilon 180 Field Flattener
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OP-19844 - Optec-4300 to Takahashi Epsilon 180 Field Flattener
About This Product
Optec now offers a complete focusing rotator option for owners of Takahashi's legendary Epsilon 180 Astrograph. Gemini's Low-Profile Focusing Rotator, coupled with the #19843 and #19844 adapters provides a drop-in replacement for the native E180 focuser.

The #19844 adapter allows owners of the Takahashi Epsilon Astrograph to insert their field flattener directly into the Gemini. Proper spacing is maintained for the E180 Field Flattener with a recessed M68 thread. First screw the Field-Flattener into the #19844 adapter, then secure the FF/Adapter assembly into the Gemini drawtube. This sets the FF at the design distance from the primary mirror and maintains the 56mm back-focus available to the camera sensor.

Inside Diameter: M68x0.75mm thread
Outside Diameter: 4.80" (122mm)
Overall Height: 0.62" (15.7mm)
Clear Aperture: 2.66" (67.6mm)
Weight: 6.8 oz (190 g)
Back-Focus Usage: 0.25" (6.35mm)
Telescope Side Connection: OPTEC-4300 male dovetail
Camera Side Connection: M68 x 0.75mm female thread

Device Compatibility:
Gemini Focusing Rotator.

Camera Side Compatibility:
Takahashi Epsilon 180 field-flattener.


QTY:  
Price as Configured: $3,595.00

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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.