William Optics Ultra-Cat 76 WIFD f/4.8 Petzval Refractor Telescope

Introducing the Ultra-Cat 76 WIFD APO Refractor!

The Ultra-Cat 76 is a high-performance 76mm apochromatic refractor, designed for astrophotographers who demand exceptional clarity and true color accuracy.

With a 5-element advanced Petzval optical design, including super ED and lanthanum glass, and a fast f/4.8 focal ratio, this telescope delivers stunningly sharp, flat-field images across its 50mm image circle. Optimized for Full Frame, APS-C, and M4/3 sensors, it also offers compatibility with Medium Format cameras for outstanding wide-field astrophotography.

An Astrophotography Powerhouse

Powered with impressive specs, the William Optics Ultra-Cat 76 offers an extensive range of targets for capture! The large 76 mm (3”) aperture soaks in the light for beautiful detail within your frames. At a 365 mm focal length, popular nebulae like the Orion Nebula, the Lagoon Nebula, and the North American Nebula are wonderful choices. In addition to nebulae, take a deeper look into space past our own Milky Way to resolve stunning detail on large galaxies like the Andromeda Galaxy and the Triangulum Galaxy. This medium-format powerhouse is built with a considerable 50 mm image circle, enabling compatibility with most of today’s largest sensors! Rapid light collection is another key benefit of this William Optics Ultra-Cat 76 thanks to its rated f/4.8 focal ratio. Included within this package are two adapters: an M54 and an M48. These additions help you seamlessly join your imaging train to your refractor, allowing you to get out and under the stars in no time!

Engineered for Excellence

This William Optics Ultra-Cat Refractor delivers superb images with its sophisticated 5-lens optical design, making it a premier instrument for astrophotography. Its innovative focuser provides a steady, solid mount for your imaging train, ensuring maximum image quality. Read more below as we highlight these impressive astrophotography capabilities and the William Optics Internal Focus Design (WIFD) included within this Ultra-Cat 76!

WIFD Focuser Design with EAF Compatibility
Instead of moving your imaging train forwards and backwards to find focus, this William Optics Ultra-Cat 76 APO refractor houses an internal focuser, moving the optics internally to find focus instead. By holding your imaging train steady, the possibility of drawtube sag is greatly diminished, especially for heavier imaging equipment. This also reduces the chance of any vignetting due to drawtube instability, resulting in higher image quality. If you’d like to automate your focusing routine, this focuser is also EAF ready!