TCF-Leo Low Profile Focuser


Include Hub
Special Takahashi Epsilon Kits
Out of Stock
Available for backorder, you can contact Optec directly at to reserve a backordered item or order here

Optec engineers have developed a 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 operates the TCF-Leo and can be extended to provide control for a second focuser and supports the 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.

The TCF-Leo supports several draw tube options including the Optec 3000 dovetail, a DSI 3.5" receiver, and a 3-inch split clamp for Wynne Correctors. You can select the option that works best for your system.

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
  • Control System: FocusLynx Controller (included if option selected)
Camera-Side Mount (based on selected option):
  • OPTEC-3000 3-inch drawtube (Default)
  • OPTEC-3000 3-inch drawtube (Extended Height)
  • DSI 3.5" receiver
  • 3-inch split clamp for Wynne Correctors
FocusLynx Controller Specifications
  • Stepper Motor Control: bipolar and unipolar stepper motors,
  • 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.
  • TCF-Leo Low Profile Focuser,
  • FocusLynx Control Hub (if hub option selected),
  • Optec USB/Serial communications cable, 6-ft. length (if hub option selected),
  • CAT-5e/CAT-6 Ethernet cable, 6-ft. length (if hub option selected),
  • 12VDC 1.25A power supply - 110-240VAC input (if hub option selected),
  • UL/CSA compliant wall plug cord (if hub option selected)

FocusLynx is compatible with all ASCOM, X2, and INDI software.

FocusLynx download page