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TCF-Leo Low-Profile Focuser

#19740 TCF-Leo 3-inch focuser with FocusLynx controller

Optec engineers have developed a new, low profile, yet extremely robust 3-inch focuser for telescope installations where back-focus is at a premium.  With the width of a typical 1-1/4" eyepiece, the TCF-Leo provides a unique focusing solution for the  Celestron EdgeHD and other telescopes with limited flange-to-focus distances.  The proven FocusLynx control system is included with every TCF-Leo and can be expanded to provide control for a second focuser.  The FocusLynx system includes optional 802.11 WiFi and Hand Control accessories.

The unique shape of the TCF-Leo is designed to fit neatly between the lock and focus knobs of the Celestron EdgeHD C-11 telescope OTA.  With a center-to-edge distance of about 2.2-inches (55mm), the TCF-Leo works exceptionally well with Innovation Foresight's On-Axis Guider, providing clearance for large cameras and filter wheels above either of the flat edges of the TCF-Leo.  Additionally, the TCF-Leo's 3600 receiver fits directly on to the large 3-inch port of the Perseus Instrument Selector for ultra-fine focus of a large format camera. 

For owners of the EdgeHD Celestron C1400 telescopes, Optec offers a set of replacement knobs for the original lock knobs which provide clearance for the TCF-Leo.  Our #19792 Sure-Lock Mirror Support Clutch upgrade includes two brass replacement lock knobs that are easily installed without tools.

Click here for additional details for the Sure-Lock replacement knob set.

With standard Optec interfaces on both telescope and camera sides, nearly any telescope imaging system can be configured.   Specify any of our OPTEC-3600 telescope mounts or contact Precise Parts for a custom adapter to fit any telescope. 

As a full 3-inch focuser, the TCF-Leo drawtube accepts any of our OPTEC-3000 adapters developed for the TCF-S3 and TCF-Lynx3 heavy duty focusers.  The optional Precision Centering Adapter allows any large 2-inch diagonal or eyepiece to be added behind the focuser.  Visual users will appreciate the FocusLynx Hand Controller with fine-focus rotary knob for no-touch operation of the telescope focus.  A special discounted price for the FocusLynx Hand Controller is available at purchse. 

TCF-Leo Specifications

  • Overall Thickness:    1.25" (31.8mm) to 1.6" (40.6mm)
  • Focuser Travel:    0.35" (8.9mm)
  • Focuser Midpoint:    1.425" (36.2mm)
  • Total Step Travel:    112,000 steps
  • Step Resolution:    0.08 microns
  • Weight:    1lb. 14 oz. (0.85 kg)
  • Payload Capacity:    20-lbs. (9 kg)
  • Telescope-side Mount:    OPTEC-3600 dovetail
  • Camera-Side Mount:    OPTEC-3000 3-inch drawtube
  • Control System:    FocusLynx Controller (included)

FocusLynx Controller Specifications

Functional Specifications:
  • Stepper Motor Control:    bipolar and unipolar stepper motors,
  • Resolution:    16-bit controller with 65,535 step range per focuser,
  • PC Connectivity:    USB/Serial, Ethernet, or optional 802.11 WiFi,
  • Hand Control:    Optional 2-button with Digital Read-Out,
  • WiFi Connection:    Optional 802.11b/g compatible,
  • Second Stepper:    Optional plug-in daughter board,
  • Input Power:    12VDC univeral power supply (110 to 230VAC input),
  • Alternative Power:    Field battery voltage (13.8VDC) with optional automotive cigarette lighter plug,
  • Software Drivers:    ASCOM local server, X2 native drivers for TheSky X
FocusLynx Port Connections:
  • Focuser 1:    RJ45 socket for standard Cat-5e/Cat-6 to focuser,
  • Focuser 2:    Optional second stepper board for RJ45 socket,
  • 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 (included).
How to Order:

Order the TCF-Leo which includes the full FocusLynx Kit.  Contact any Optec dealer, call Toll-Free 1-888-488-0381, email, or click the button below to order directly through Paypal.

Package includes:

  • TCF-Leo Low Profile Focuser,
  • FocusLynx Control Hub,
  • Optec USB/Serial communications cable, 6-ft. length,
  • CAT-5e/CAT-6 Ethernet cable, 6-ft. length,
  • 12VDC 1.25A power supply - 110-240VAC input,
  • UL/CSA compliant wall plug cord

Additional Details:

FocusLynx control hub details can be found here.

TCF-Leo installation instructions are available here.