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March 14th: The store will be closed on Friday as we will be out all night to observe and image the total lunar eclipse! Good eclipse!
March 14th: The store will be closed on Friday as we will be out all night to observe and image the total lunar eclipse! Good eclipse!
William Optics Cat 91 WIFD (Pre-order, ships in one week)

William Optics Cat 91 WIFD (Pre-order, ships in one week)

by William Optics
SKU WO-T-C-91
$0
$2,598.00 USD - $2,598.00 USD
$2,598.00
$2,598.00 USD - $2,598.00 USD
$2,598.00 USD
  • Petzval Design, No Backfocus Hassles
  • Full-Frame & Medium-Format Ready, No Extra Flattener Needed
  • Fast f/4.9 Focal Ratio
  • Seamless WIFD Focusing
Availability:
Backordered
Contact us to know when we will receive our next ones!
Availability:
Backordered
Contact us to know when we will receive our next ones!

Free Shipping in USA

More information

  • Step up your astrophotography game with the William Optics RedCat 91, an advanced apochromatic refractor tailored for full-frame and medium-format cameras. This latest addition to the RedCat series combines portability with superior optical performance, making it a versatile tool for capturing breathtaking detail in deep-sky objects.
    An advanced apochromatic refractor tailored for full-frame and medium-format cameras. This latest addition to the RedCat series combines portability with superior optical performance, making it a versatile tool for capturing breathtaking detail in deep-sky objects.

    Advanced Petzval

    Researched and developed by WO, the innovative 5-element Petzval design redefines telescope optics. This advanced system achieves a flawless spot diagram across a medium-format image circle.

    William Optics Petzval

    Extra-low Dispersion (ED) glasses

    Extra-low Dispersion (ED) glasses

    Needs no flattener

    The Petzval design inherently flattens the field, eliminating the need for an external field flattener.

    https://williamoptics.com/cdn/shop/files/series-Diagram_Cat-91_1.jpg?v=1728272268&width=800

    Never easier to capture deep sky objects

    https://williamoptics.com/cdn/shop/files/FOV-cat91-C-02.jpg?v=1730707560&width=1600

    Compatible with Electronic Motorized Devices

    Hassle Free Installation ( No Mounting Bracket Kit required )

    https://williamoptics.com/cdn/shop/files/Cat-91-WIFD-EAF.jpg?v=1730708811&width=1000

    Wo patented design

    The Cat 91 holds three unique patents, ensuring easy and perfect focusing along with precise coaxial image quality, preventing draw tube tilt issues caused by optical misalignment.

    The WIFD focusing Design relocates the focuser to the center of the telescope, addresses the issue of tube tilt caused by the weight of accessories and cameras.

    https://williamoptics.com/cdn/shop/files/WIFD-grey_line.gif?v=1727934296&width=800

    CAT Handle Bar

    Crafts for enhanced portability and versatility.
    Designed for seamless functionality without compromising on stability. Engineered with wide surface contacts, this innovative ring ensures a secure fit while enabling fast, easy detachment.

    https://williamoptics.com/cdn/shop/files/Cat-91-WIFD-whatsinbox-mounting.png?v=1728630077&width=800

    Integrated Bahtinov mask

    Laser engraved on high-definition and stable optical PMMA. Enhances astrophotography experience with quick and accurate adjustments.

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