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William Optics M92 to M63 Adapter for William Optics FLT91

William Optics M92 to M63 Adapter for William Optics FLT91

by William Optics
SKU WO-YE-M92-63
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$88.00 USD
$88.00 USD - $88.00 USD
$88.00 USD
$83.60 USD
$83.60 USD - $83.60 USD
$83.60 USD
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  • Connects William Optics FLT91 Telescope to Flat6AIII Flattener
  • Input Thread: M92 Male
  • Output Thread: M63 Female
  • Optical Path Length: 10.5 mm
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • M92 to M63 Adapter for William Optics FLT91

    This 10.5 mm M92 to M63 adapter connects a William Optics Flat6AIII flattener/reducer to an FLT91 refractor.

    A Purpose-Built Connection for the FLT91 and Flat6AIII at 10.5mm

    This adapter is for using the Flat6AIII flattener/reducer on the FLT91 telescope.

    • Telescope-Side Connection: The male M92 thread attaches directly to the focuser drawtube of the FLT91 telescope.
    • Flattener-Side Connection: The female M63 thread accepts the nosepiece of the Flat6AIII flattener/reducer.
    • Optical Length: The adapter adds 10.5 mm to the optical path.

  • What is the primary purpose of this M92 to M63 Adapter?

    This adapter is designed specifically to connect the William Optics FLT91 telescope to the Flat6AIII flattener/reducer. It has an optical length of 10.5 mm.

    How do I use this adapter with my William Optics FLT91 and Flat6AIII?

    You thread the M92 male side of the adapter directly onto the focuser of your FLT91 telescope. Then, you thread the Flat6AIII flattener into the M63 female side of the adapter. This configuration establishes the correct mechanical and optical connection between the two components.

    Is this M92 to M63 adapter a universal part for other telescopes?

    It is sold only as the adapter for the Flat6AIII on the FLT91. Its M92 male and M63 female threads may fit other equipment, but check the spacing your own optics require.

    Does installing this adapter set the final back focus for my FLT91 imaging train?

    No. This adapter only joins the flattener to the telescope. You must still add the correct spacers between the flattener and your camera sensor to meet the flattener's own back focus requirement (typically 55 mm, but always check your flattener's manual).

    What are the exact thread specifications for this adapter?

    The adapter features the following threads:

    • Light-In Side (Telescope): M92 male thread
    • Light-Out Side (Accessory): M63 female thread
  • Light-In Side Thread M92 (male)
    Light-Out Side Thread M63 (female)
    Optical Length 10.5 mm
    Kind Thread converter
    Telescope-Side Connection M92 male
    Camera-Side Connection M63 female

    • M92 to M63 Adapter

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  • William Optics 2-Year Warranty