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Starlight Instruments 3.5" End Cap - for Astro-Physics Telescope Accessories
Starlight Instruments 3.5" End Cap - for Astro-Physics Telescope Accessories
Starlight Instruments 3.5" End Cap - for Astro-Physics Telescope Accessories

Starlight Instruments 3.5" End Cap - for Astro-Physics Telescope Accessories

by Starlight Instruments
SKU SI-EC35-505AP
CA$224.00 - CA$224.00
CA$224.00
CA$224.00 - CA$224.00
CA$224.00
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  • Adapts 3.5" Feather Touch focusers to Astro-Physics accessories
  • Provides a secure 2.7" x 24 tpi female threaded connection
  • Eliminates flexure and tilt with heavy imaging trains
  • Compatible with Baader quick-lock accessories using the A/P thread
  • Machined from high-quality aluminum by Starlight Instruments
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  • Description
  • FAQ
  • In the Box
  • Warranty

  • Starlight Instruments 3.5" End Cap - for Astro-Physics Telescope Accessories

    This Starlight Instruments 3.5" End Cap creates a rigid, direct-threaded connection between a 3.5" Feather Touch focuser and the extensive range of Astro-Physics accessories using a 2.7" male thread. Featuring a precision-machined 2.7" x 24 tpi female thread, this adapter ensures a secure, flex-free attachment point critical for supporting heavy cameras, field flatteners, and reducers without introducing tilt.

    Secure 2.7" x 24 tpi Threading for 3.5" Feather Touch Focusers

    For imagers, a threaded connection is non-negotiable for maintaining perfect optical alignment. This end cap replaces the standard compression ring on a 3.5" Feather Touch focuser, providing a robust metal-on-metal interface for Astro-Physics accessories. It is also fully compatible with Baader Planetarium quick-lock accessories that utilize the same Astro-Physics 2.7" thread standard, expanding its utility in your imaging train.

    • Zero Flexure: The direct-thread design is essential for astrophotography, preventing the subtle shifts and tilts that can occur with compression fittings when supporting a heavy camera and filter wheel.
    • In-House Quality: Machined from a single piece of high-grade aluminum and finished at Starlight Instruments' facility, this end cap matches the precision and aesthetic of their Feather Touch focusers.
    • Broad Compatibility: Connects seamlessly to popular Astro-Physics accessories like the CCDT67 Telecompressor Reducer or any component terminating in a 2.7" male thread.

  • What is the purpose of the Starlight Instruments 3.5" End Cap for Astro-Physics accessories?

    This end cap allows you to securely attach accessories with a male Astro-Physics 2.7" x 24 tpi thread to a 3.5" Starlight Instruments Feather Touch focuser. It creates a rigid, non-flexing connection ideal for astrophotography.

    Which focusers is this 3.5" End Cap compatible with?

    This end cap is designed specifically for the Starlight Instruments 3.5" Feather Touch focuser (FTF35xx series). It will not fit their 2", 2.5", or 3" models.

    Can I use this Starlight Instruments End Cap to connect my Astro-Physics CCDT67 reducer to a 3.5" Feather Touch focuser?

    Yes, absolutely. The Astro-Physics CCDT67 0.67x Telecompressor Reducer uses the standard 2.7" male thread, making this end cap the perfect adapter for attaching it rigidly to your 3.5" Feather Touch focuser for imaging.

    Will this end cap work with my Baader Planetarium ClickLock clamp that has an Astro-Physics thread?

    Yes. Baader produces accessories, including their ClickLock and Quick-Lock clamps, that use the Astro-Physics 2.7" thread standard. This end cap will allow you to connect those components directly to your 3.5" Feather Touch focuser.

    What are the thread specifications for this Starlight Instruments end cap?

    The internal thread on this end cap is a female 2.7" x 24 threads-per-inch (tpi) thread. This is the standard thread used by Astro-Physics for many of their larger format accessories.

    Why choose this threaded end cap over a standard 2" compression ring adapter on my 3.5" Feather Touch focuser?

    While a compression ring is convenient for visual use and swapping eyepieces, a threaded connection is far superior for imaging. It provides a solid, metal-to-metal lock that eliminates any possibility of tilt or flexure, which is crucial for maintaining a flat field with a heavy camera, filter wheel, and other accessories attached.

    • Starlight Instruments 3.5" End Cap for Astro-Physics Accessories

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  • Starlight Instruments 2-Year Warranty