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Starlight Instruments Focus Motor for RedCat/SpaceCat
Starlight Instruments Focus Motor for RedCat/SpaceCat
Starlight Instruments Focus Motor for RedCat/SpaceCat

Starlight Instruments Focus Motor for RedCat/SpaceCat

by Starlight Instruments
SKU SI-RCEF
CA$371.00 - CA$371.00
CA$371.00
CA$371.00 - CA$371.00
CA$371.00
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  • Adds electronic focus control to William Optics RedCat/SpaceCat telescopes
  • Based on the proven Starlight Instruments Handy Stepper Motor (HSM)
  • Enables automated, repeatable focusing for astrophotography
  • Requires a Starlight Instruments EFS or Focuser Boss II controller
  • Eliminates focus shift from manual helical focuser adjustments
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  • Description
  • FAQ
  • Downloads
  • Warranty

  • Starlight Instruments Focus Motor for RedCat/SpaceCat

    The Starlight Instruments SI-RCEF Focus Motor brings automated, high-precision focusing to the helical focuser of the William Optics RedCat and SpaceCat 51mm astrographs. By motorizing the manual focuser, this system allows you to achieve critical focus using software control, eliminating image shift and enabling advanced automated imaging routines that are impossible with manual adjustment alone.

    Automated Focusing for the RedCat/SpaceCat 51mm

    The William Optics RedCat 51mm is a premier wide-field imaging instrument, but its manual helical focuser can be challenging for achieving the perfect, repeatable focus required for serious astrophotography. This Starlight Instruments motor drive replaces manual guesswork with robotic precision, making it an essential upgrade for imagers.

    Based on a modified version of the reliable Handy Stepper Motor (HSM), the SI-RCEF provides the fine, backlash-free adjustments necessary to nail focus across temperature changes and between filter swaps. This allows your imaging software to run autofocus V-curves, ensuring your stars remain perfectly sharp throughout the entire night.

    A Dedicated Starlight Instruments Ecosystem

    This focus motor is designed to integrate seamlessly into the Starlight Instruments control ecosystem. A key trade-off for its precision is that it cannot be operated as a standalone device; it requires either the Starlight Instruments Electronic Focusing System (SI-EFS) or the Focuser Boss II controller to function.

    This requirement ensures that the motor operates with the sophisticated backlash compensation, temperature compensation, and ASCOM-compliant software control that Starlight Instruments is known for. By connecting to a dedicated controller, you gain access to a robust platform for managing your entire imaging workflow.

    Choosing Your Controller: EFS vs. Focuser Boss II

    The choice between the EFS and Focuser Boss II depends on the scale of your imaging setup. Both provide flawless control for the RedCat motor, but serve different needs.

    • Electronic Focusing System (EFS): This is the ideal choice for a streamlined, single-focuser setup. The compact control box and simple hand controller are perfect for portable rigs where the RedCat is the primary instrument. It provides full ASCOM compatibility for computer control in a minimalist package.
    • Focuser Boss II: If your RedCat is part of a larger observatory setup or you plan to control multiple focusers (e.g., a main scope and a guidescope), the Focuser Boss II is the superior hub. It offers Ethernet and optional WiFi connectivity, can control a second focuser, and features a built-in web server for control from any device.

  • What is the purpose of the Starlight Instruments Focus Motor for the RedCat?

    Its purpose is to replace manual focusing on the William Optics RedCat/SpaceCat 51mm telescopes with precise, repeatable electronic focus control. This is critical for astrophotography, as it allows autofocusing software to maintain perfect focus as temperatures change overnight.

    Which controller do I need for the RedCat Focus Motor?

    You must use a Starlight Instruments controller. You have two options: the Starlight Instruments Electronic Focusing System (SI-EFS) for single-focuser setups, or the more advanced Focuser Boss II, which can control multiple devices and offers network connectivity.

    Will this motor work with other helical focusers?

    No, the SI-RCEF motor assembly is specifically designed and machined to fit the helical focuser of the William Optics RedCat 51mm and SpaceCat 51mm telescopes only. It is not a universal motor.

    How does the RedCat Focus Motor improve imaging of faint targets like the California Nebula (NGC 1499)?

    For long-exposure projects like NGC 1499, temperature drops can cause focus to drift, softening your images. With this motor and an autofocus routine in software like NINA or SGP, your system can automatically run a focus check every hour or after a filter change, ensuring every sub-exposure is perfectly sharp and maximizing the detail you capture.

    Can I still focus my RedCat 51mm manually with the motor installed?

    The Starlight Instruments Handy Stepper Motor (HSM) family, on which this motor is based, typically includes a manual override feature. By rotating the motor housing, you can disengage the gears for manual adjustment. This is useful for initial setup or visual use without powering on the controller.

    Is installing the Starlight Instruments Focus Motor on my RedCat difficult?

    Installation is straightforward for users comfortable with basic tools. The motor assembly is designed to clamp securely onto the telescope's helical focuser mechanism. Starlight Instruments provides detailed instructions to guide you through the process.

  • Starlight Instruments 1-Year Warranty on Electronics