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

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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)
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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.

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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-19839 - Optec-4300 Extension Adapter, 25mm Length
OP-19839 - Optec-4300 Extension Adapter, 25mm Length
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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-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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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:
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Camera Side Compatibility:
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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.

QTY:  
Price as Configured: $3,595.00

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Focusing Rotator Physical Specifications:
  • Clear Aperture: 3.75" (95mm)
  • Back-Focus Usage: 2.2" to 2.7" (55.9 to 68.6mm)
  • Focuser Travel: 0.5" (12.7mm)
  • Focuser Resolution: 0.11 microns per step
  • Rotator Resolution: 600 steps per degree
  • Minimum Overall Thickness: 2.2" (55.9mm) [Full IN position]
  • Dimensions: 9.4" x 7.4" (239mm x 187mm)
  • Weight: 6 lb. 6 oz. (2.9 kg)
Controller Hub Specifications:
  • Length: 5.1" (130mm)
  • Width: 3.2" (81mm)
  • Height: 1.0" (27mm)
  • Weight: 10 oz. (285 g)
  • Mounting Holes: Four 4-40 x 1/8" depth (reverse side)
  • Case Material: 6061 aluminum, anodized black.
Gemini Hub Port Connections:
  • Focuser: RJ45 socket for standard Cat-5e/Cat-6 cable to Focuser port
  • Rotator: RJ45 socket for standard Cat-5e/Cat-6 cable to Rotator port
  • Power: 12VDC input, 2.5 x 5.5mm plug, center pin positive
  • Network: Standard RJ45 Ethernet socket
  • Hand Controller: RJ22 socket for standard telephone handset cord
  • Serial: RJ12 socket for Optec USB/Serial cable
  • Wireless: 802.11 WiFi option