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Starlight Instruments 3.0" Adapter for RCOS Telescopes

by Starlight Instruments
SKU SI-A30-1903-18
$250.00 USD - $250.00 USD
$250.00 USD
$250.00 USD - $250.00 USD
$250.00 USD
Price Match Policy!
  • Connects 3.0" Feather Touch focusers to RC Optical Systems telescopes
  • Ensures a rigid, zero-flexure connection for astrophotography
  • Precision-machined for perfect mechanical alignment
  • Official Starlight Instruments factory component
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Starlight Instruments 3.0" Adapter for RCOS Telescopes

    The Starlight Instruments 3.0" Adapter for RCOS Telescopes provides the dedicated mechanical interface required to upgrade Ritchey-Chrétien Optical Systems instruments with a 3.0" Feather Touch focuser. This adapter is essential for attaching the large-format 3.0" focuser, enabling precise, repeatable focus for heavy imaging trains.

    Secure Mounting for 3.0" Feather Touch Focusers

    This is not a generic, third-party component; it is a factory part from Starlight Instruments, engineered to provide a perfect fit between their 3.0" Feather Touch focuser and the rear cell of an RCOS telescope. Using the correct, manufacturer-specified adapter is critical for maintaining the tight mechanical tolerances demanded by high-resolution Ritchey-Chrétien optics.

    The adapter guarantees a secure, perfectly aligned connection that prevents tilt and flexure. This rigidity is the key to unlocking the full potential of your imaging system, ensuring that the focuser can support a heavy camera and filter wheel without compromising the optical alignment or the quality of your data.

  • How do I install the Starlight Instruments 3.0" Adapter for RCOS Telescopes?

    The adapter's male 4.0625" x 24 TPI thread screws directly into the rear port of a compatible RC Optical Systems telescope. The Starlight Instruments 3.0" Feather Touch focuser then attaches securely to the adapter, completing the mechanical connection.

    Is this adapter compatible with any focuser other than the Starlight Instruments 3.0" Feather Touch?

    No. This adapter is specifically machined to match the proprietary mounting pattern and dimensions of the Starlight Instruments 3.0" series of focusers. It is not intended for use with focusers from other manufacturers.

    I have an older RCOS telescope. How can I confirm this adapter will fit?

    This adapter is designed for RCOS telescopes with a 4.0625" x 24 TPI rear cell thread. Because thread standards can vary between models and production years, we strongly recommend contacting Starlight Instruments with your telescope's details to confirm compatibility before purchasing.

    Why do I need this specific Starlight Instruments adapter for my RCOS scope instead of a generic one?

    A generic adapter risks thread damage, flexure, or optical misalignment. This official Starlight Instruments adapter guarantees a perfect mechanical fit and alignment, protecting your investment and ensuring the high-resolution performance of your RCOS optical system is not compromised by a weak link in the imaging train.

  • Kind other (state): scope-specific tube adapter for a 3.0in Feather Touch focuser
    Telescope-side connection thread: other (state): 4.0625in x 24 TPI; gender: male
    Camera-side connection thread: other (state): Starlight 3.0in Feather Touch focuser (FTF3015B-A); gender: None
    Warranty 2 years

    • 3.0" Adapter for RCOS Telescopes

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  • Starlight Instruments 2-Year Warranty