Telescope-Refracting Telescopes-William Optics WIFD Ultra-Cat 108 APO Refractor

Introducing the Ultra-Cat APO 108, the Ultimate Refractor for Astrophotography!

If you’re in search of top-tier imaging performance, this William Optics Ultra-Cat 108 is the telescope for you. With 5 internal lens elements composed of high quality glass, you can expect stunningly sharp, well-corrected astrophotos! Also, the large 108 mm (4.25”) aperture collects a copious amount of light for outstanding contrasts and resolution of detail. As a Petzval refractor, there is no need for an additional field flattener nor backspace calculation, making camera attachment a breeze. Stars will be sharp across the entire field of view, even for medium-format and full frame cameras! Thanks to the innovation from William Optics, this Ultra-Cat 108 APO Refractor is sure to take your astrophotography to the next level.

The large 108 mm aperture paired with the 518 mm focal length results in a focal ratio of f/4.8, making this a speedy system for deep space imaging. Featuring an incredibly large image circle of 60 mm, the William Optics Ultra-Cat 108 supports medium-format and full frame cameras for stunning wide field images. In addition to these superior optics, this APO telescope comes furnished with the William Optics Internal Focus Design (WIFD) for smooth, stable focusing. You even have the ability to attach an electronic autofocuser (not included) to this telescope for automatic, hands-free focusing. With features like these, the William Optics Ultra-Cat 108 is the ultimate tool for astrophotographers eager to capture breathtaking images of our universe.

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Crafted with 5 Internal Lenses for Unparalleled Performance

This William Optics Ultra-Cat 108 is built with quality in mind, housing a total of five lens elements with one ED and two Super ED glass elements. These lenses work together to eradicate coma, field curvature, and any other aberrations, resulting in unparalleled color correction and clarity. Supporting medium-format and full-frame cameras, you can expect edge-to-edge sharpness across the entirety of the 60 mm image circle. With these outstanding optics, easily resolve stunning structure within galaxies, beautiful detail within nebulae, and stark definition of star clusters!

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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 108!

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An Astrophotography Powerhouse
Unlocking a world of imaging possibilities, this William Optics Ultra-Cat 108 is a must have for those looking to capture outstanding astroimages. The 518 mm focal length is perfect for filling the frame with the Pleiades Open Star Cluster, the Orion Nebula, the Andromeda Galaxy, and near countless others. Not only will your images be bright thanks to the large 108 mm aperture, but the f/4.8 focal ratio ensures you’ll gather plenty of light in a short amount of time. Included within this package are three adapters: an M68, an M54, and an M48. These included adapters help you seamlessly join your imaging train to this William Optics Ultra-Cat, allowing you to get out and under the stars in no time.

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WIFD Focuser Design with EAF Compatibility
Instead of moving your imaging train forwards and backwards to find focus, this William Optics Ultra-Cat 108 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!