The William Optics Ultra-Cat 76 WIFD – 30th Anniversary Limited Edition is a celebratory reissue of one of the most advanced apochromatic telescopes, created to celebrate the 30th anniversary of William Optics. The Cat series has always been groundbreaking in the brand's history – from the RedCat 51, which revolutionized the small refractor market in 2019, to the launch of the new Ultra-Cat line in 2025, based on the advanced five-element Petzval optical system. The Ultra-Cat 76 Anniversary Edition combines compact size with excellent image quality and the iconic character of a limited edition.

The manufacturer has created only 100 individually numbered telescopes , each distinguished by a unique laser engraving featuring a cat embracing the number "30." Each telescope receives a special anniversary certificate and a dedicated 32mm UniGuide finder, complementing the anniversary set. This is not only an astrophotography instrument, but also a unique symbol of thirty years of innovation and passion for the sky.

Key features

• anniversary edition limited to 100 numbered copies
• special anniversary engraving "30 Years of William Optics"
• certificate commemorating the 30th anniversary of the company
• additional UniGuide 32 mm finder included
• 76 mm Advanced Petzval lens (5 elements)
• Super ED, ED, lanthanum and X-Element glass
• fast f/4.8 optics with a focal length of 365 mm
• flat image field – no need to use a flattener
• 50 mm image diameter – full support for Full Frame cameras
• internal WIFD (Rack & Pinion) extractor compatible with ZWO EAF
• built-in Sensor Tilt Xterminator (STX) rotator
• reduction of thermal expansion effect (Anti-Shrink Lens Cell)
• built-in Bahtinov focusing mask
• compatible with Canon EF/RF, Nikon F/Z, Sony E, Pentax K, MFT, FUJI X mounts
• elegant, anodized housing with a carrying handle

Set components

• William Optics Ultra-Cat 76 WIFD optical tube – Anniversary Edition
• Sensor Tilt Xterminator rotator
• M54, M48 adapters
• built-in Bahtinov mask
• William Optics UniGuide 32 mm finder (anniversary accessory)
• 30th anniversary certificate with an individual telescope number

Note: T-Mount bayonet adapters for cameras (Canon EF/RF, Nikon F/Z, Sony E, Pentax K, MFT, FUJI X) are not included in the set - they must be purchased separately.

Technical parameters

• lens diameter: 76 mm
• optical system: 5-element Petzval
• glass types: 2× Super ED, 1× ED, 1× Lanthanum glass, 1× X-Element
• focal length: 365 mm
• aperture: f/4.8
• image diameter: 50 mm
• lift construction: WIFD (Rack & Pinion, internal)
• EAF compatibility: yes
• tube length: 363.3 – 408.8 mm
• tube weight: 4.31 kg
• camera mount: Canon EF/RF, Nikon F/Z, Sony E, Pentax K, MFT, FUJI X
• dedicated to sensors: Full Frame, APS-C, M4/3, compatible with medium format
• manufacturer: William Optics

Guarantee

24 months