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Gemini Focusing Rotator

$3,495.00

Gemini Focusing Rotator

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 andCelestron 10-inch and larger class SCT, and Plane Wave Secure-Fit. 

Customer Images:

Charles Miller supplied this Veil image taken through his new Gemini focusing rotator mounted to his 12" Meade LX850 OTA.  Charlie took delivery of his Gemini in May 2015.

"In the attached image of the Veil Nebula, the imaging run was about 4 hours and the temperature dropped about 10 C. The image consists of 48 subs of 5 minutes; 16 each in unbinned RGB. I was very pleased to see how well the Gemini's TC held the focus during the entire four hours. Congrats on a great product!"

Image courtesy Charles Miller - August 2015.

OPTEC-4300 4.3-inch Adapters

The new OPTEC-4300 standard dovetail mounting system is being developed quickly to support a large stable mounting connection between telescope and camera. 

Click the button at right for a full selection of both telescope-side and camera-side OPTEC-4300 adapters. 

For other telescope OTA's,  PreciseParts can supply additional custom adapters while the larger OPTEC-4300 adapter line is developed and expanded. 

More Information and Ordering Information

For additional details and ordering information, click the Gemini button at right or click here.

★ Judge.me Reviews

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Imaging Made Easy

Prism is my GoTo program for observatory control and imaging. Prism's many features make imaging taking a breeze.

I was concerned about giving Prism a try , especially as its quite expensive. So far Im very impressed and glad of my decision.
Im a beginner at all this so haven't tried other more recommended software, Prism appealed as it seems to do everything instead of using several programs 👍🏻

Great lightweight guide scope

This guide scope replaces a 400/80 that was waaay too heavy for what it did. The smaller 60mm scope does a great job guiding and I can RA balance with just one counter weight now - much better - and it looks like something Ferrari designed

Still learning Prism using Wireless links...

I have much of your software working at this time... I have it parked on my main computer, and a notebook... My main computer is a OverClock computer with 32 Gigs of RAM Clocking presently at 4400MHz with software parked on SSD drives... The rotation dome by NexDome is still not working... Most problems like this have to do with ASCOM Drivers... There is not very much detail information on how to use this software... I have to feel my way to a total operational staus... Second issue... The rain in the San Francisco Bay Area this year has limited my access to my larger telescope (12 inch SCT)... This rain has been so significant, I was force to weatherize my observatory... My goal here is,,, I am trying to remotely control my observatory totally. I have used Netgear Powerline 2000 to handle camera images and discover controlling rules to do that... High speed is vital for images with cameras over 3 Megs... I have both 12 Mega sensors and 24 Mega sensors... I am also using Netgear Nighthawk router and its mating extender to increase control signals to my observatory that is about 100 feet on the side of hill... I am also using Virtual Here software on a Raspberry Pi inside the observatory to solve the USB interface requirements... I started out using Model B and B+ on level 3 raspberry Pi's... I have moved to Level 4 Raspberry Pi to gain access to USB 3.0 technology... Big difference! I hope by early spring to have everything working... Bob Ritter MicTechS

A great program, even for beginners!

I have to admit, I was hesitant to invest in an “all in one” astrophotography program. Being a beginner, I thought the learning curve would be way too steep, but after talking with several friends I decided to give it a try. The first thing I noticed was the logical layout of the main screen. It was very intuitive and easy to navigate. Everything you could need for astrophotography is in this program! Setup of my equipment was quick and easy with no glitches or errors. Everything runs smoothly from capture to the final process. You will surely have questions and this brings me to the next point. Prism’s customer service is second to none! With on line tutorials, a Facebook group and email you will have instant access to knowledgeable users worldwide. My first question was answered directly by the US distributor within a matter of minuets! Take the next step and invest in your future in astrophotography! You’ll never look back!

Greg Hemmings