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Starlight Instruments 2.5" End Cap w/ 2.0" Compression Ring Opening and M47X.75 Thread

by Starlight Instruments
SKU SI-EC25-2005-5
CA$280.00 - CA$280.00
CA$280.00
CA$280.00 - CA$280.00
CA$280.00
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  • Adapts 2.5" Feather Touch focusers for visual and imaging use
  • Features a standard 2.0" compression ring opening
  • Includes a female M47x0.75 thread for secure accessory attachment
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Starlight Instruments 2.5" End Cap w/ 2.0" Compression Ring Opening and M47X.75 Thread

    The Starlight Instruments 2.5" End Cap outfits a 2.5" Feather Touch focuser with both a 2.0" compression ring opening and a female M47x0.75 thread. With this dual design, you can switch between standard 2.0" eyepieces and specific M47x0.75 threaded imaging accessories without changing hardware on your optical tube.

    A Dual-Purpose End Cap: 2.0" Compression and M47x0.75 Threads

    This end cap integrates two common connection standards into a single, precision-machined component for your 2.5" Feather Touch focuser. For visual observation, the 2.0" compression ring opening holds your diagonal or eyepieces. For astrophotography, the female M47x0.75 thread provides a rigid, direct-threaded connection for compatible field flatteners, reducers, or camera adapters, ensuring your imaging train remains perfectly aligned.

    M47x0.75 vs. Standard 2" End Caps: The Imaging Advantage

    While a standard 2.0" compression ring end cap can hold a camera via its 2" nosepiece, this slip-fit connection is susceptible to tilt and flexure, especially with heavier cameras. The primary advantage of this M47x0.75 threaded end cap is the elimination of that risk. By threading your corrector or camera directly to the focuser drawtube, you create a solid, stable connection that preserves the optical alignment critical for achieving sharp, round stars across the entire field of view.

  • Which Starlight Instruments focusers is this 2.5" End Cap compatible with?

    This end cap is designed specifically for Starlight Instruments 2.5" Feather Touch focusers, such as the FTF25xx series. It provides a direct replacement for other 2.5" end caps.

    What is the main benefit of the M47x0.75 thread on this End Cap?

    The M47x0.75 thread allows for a rigid, secure connection to imaging accessories like field flatteners, reducers, and cameras. This threaded attachment prevents tilt and flexure that can occur with slip-fit compression rings, which is essential for critical astrophotography.

    Can I still use my 2.0" eyepieces and diagonal with this M47x0.75 threaded End Cap?

    Yes. The end cap features a standard 2.0" compression ring opening, allowing you to use all your standard 2" visual accessories just as you would with a non-threaded end cap.

    How would this M47x0.75 End Cap benefit my setup with a large refractor and a 2.5" Feather Touch focuser?

    For a large refractor like a Takahashi or Astro-Physics equipped with a 2.5" Feather Touch focuser, this end cap is ideal. It provides a direct threaded path for specific reducers or flatteners that use the M47 thread, ensuring perfect optical spacing and alignment for a flat, corrected field from edge to edge.

    If I'm imaging planets with a Celestron EdgeHD 9.25 and a 2.5" Feather Touch, is this End Cap necessary?

    While a standard 2" compression ring works for planetary imaging, this M47x0.75 threaded end cap offers a more robust solution. If your camera train includes heavy components like a filter wheel and an ADC, the threaded connection provides superior rigidity, preventing any sag that could shift the focus point during an imaging run.

  • Kind other (state): focuser end cap
    Telescope-side connection thread: other (state): 2.5in Feather Touch drawtube (end cap thread); gender: None
    Warranty 2 years

    • Starlight Instruments 2.5" End Cap w/ 2.0" Compression Ring Opening and M47X.75 Thread

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  • Starlight Instruments 2-Year Warranty