William Optics Mighty-Cat 71 f/3.2 Limited Edition Refractor Telescope
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- 7-Element EVO Petzval w/ Super ED glass. No need to calculate back focus
- Built-in Sensor Tilt Xterminator w/ Rotator. Including M48 and M54 camera adapters
- Can support up to large full-frame camera sensors
- WIFD Rack & Pinion focuser - (EAF ready)
- Self-flattening design. No need for a separate field flattener
Limited Edition Mighty-Cat 71: Celebrate 30 Years of William Optics Excellence!
The William Optics Mighty-Cat 71 30 Years Anniversary Limited Edition is a 71mm astrograph engineered to redefine ultra-fast deep-sky imaging. Celebrating three decades of optical innovation, this exclusive 100-set limited run features a custom "Cosmic Visitor" design with intricate extraterrestrial modifications—a tribute to 30 years of peering into the unknown and chasing the mysteries of the universe. It introduces an unprecedented, record-breaking f/3.2 focal ratio—the fastest telescope William Optics has ever created—while featuring a 43.2mm image circle and the patented WIFD internal focusing system.
This ultra-fast optical system drastically reduces exposure times, helping capture faint nebulae, dark dust lanes, and expansive celestial structures in a fraction of the time. With its flat-field 7-element optics, stable internal focusing, and unique design that hints at technology from another world, the Mighty-Cat 71 Anniversary Edition is built for demanding deep-sky imaging with modern full-frame and cropped-sensor camera systems.
Mighty-Cat 71 Standout Features
Built-In Bahtinov Mask
Integrated bahtinov mask into the front cap for quick and accurate focusing, making precise star focus easier in the field.
Adventure Ready
Including a padded soft carrying case tailored specifically for the Mighty-Cat 71. Features precision-cut spacing to securely house the telescope with its heavy-duty mounting ring, handlebar, and dual-sided dovetail plate still attached.
Sensor Tilt Xterminator
Features a heavy-duty rear tilt and rotation interface designed to support modern imaging setups, reducing the chance of rear-end sag while retaining convenient sensor-squaring capability.
30th Anniversary Limited Edition Build
This special telescope was made to celebrate 30 years of William Optics designs. It uses high-quality metal parts that are precisely cut to fit together perfectly. Inside the telescope, a feature called Anti-Shrink Lens Cell Technology protects the glass. When you take photos outside on freezing cold nights, metals naturally shrink and expand, which can squeeze the telescope glass and blur your photos. This technology stops that from happening, keeping the glass perfectly lined up so your long-exposure photos stay sharp and clear all night.
7-Element Petzval Optical Design
The Mighty-Cat 71 features a fast f/3.2 focal ratio and 230mm focal length, making it the fastest optical system in the company's history. Its 7-element Advanced Petzval layout incorporates two Super ED glass elements, two Lanthanum elements, and three specialized X-elements to eliminate chromatic aberration. This design inherently corrects for field curvature, providing a flat 43.2mm full-frame image circle that delivers pin-sharp stars across large camera sensors without requiring a separate external field flattener.
Patented WIFD Focuser
For heavy camera loads, the telescope utilizes the patented WIFD (William Optics Internal Focuser Design) rack-and-pinion system. Shifting lens elements internally over a 0–35mm range instead of extending an external drawtube removes focus flexure, prevents sensor tilt, and eliminates mechanical vignetting. The ready-to-image package includes an integrated Sensor Tilt Xterminator (STX-R), an M54/M48 camera adapter stack, a patented multi-use handlebar for accessories, and a dual-sided Vixen/Arca-Swiss dovetail plate, all packaged in a custom-fitted protective soft carrying case.
Specifications
-
Optical Design: 7-Element Advanced Petzval
-
Lens Elements:
-
2x Super ED
-
2x Lanthanum
-
3x Special X-Glass components
-
-
Focal Length: 230 mm
-
Aperture: 71 mm (2.8 in)
-
Focal Ratio: f/3.2
-
Image Circle: 43.2 mm (Full-frame)
-
Focuser: WIFD Internal Rack & Pinion (ZWO EAF electronic focuser ready)
-
Focuser Travel: 0 mm to 35 mm (0 in to 1.38 in)
-
Adapters Included: Sensor Tilt Xterminator (STX-R) Rotator, M54 Camera Adapter, and M48 Camera Adapter
-
Optional Flattener: None required (Flat field is built directly into the 7-element Petzval design)
-
Camera Format Support: Full Frame, APS-C, and Micro 4/3 (M4/3)
-
T-Mount Support: Canon EF/RF, Nikon F/Z, Sony E, Pentax K, MFT (M4/3), and FUJI X
-
Dovetail Type: Reversible Vixen & Arca-Swiss
-
Optical Tube Length: 315 mm (12.4 in)
-
OTA Weight: 3.38 kg (7.45 lbs)
-
Total Weight: 4.1 kg (9.04 lbs) w/ included accessories
Diagram Reports
Wavelength Chart
Spot Diagram Chart
Other Information
- Country of Manufacture: Taiwan
Limited Edition Mighty-Cat 71: Celebrate 30 Years of William Optics Excellence!
The William Optics Mighty-Cat 71 30 Years Anniversary Limited Edition is a 71mm astrograph engineered to redefine ultra-fast deep-sky imaging. Celebrating three decades of optical innovation, this exclusive 100-set limited run features a custom "Cosmic Visitor" design with intricate extraterrestrial modifications—a tribute to 30 years of peering into the unknown and chasing the mysteries of the universe. It introduces an unprecedented, record-breaking f/3.2 focal ratio—the fastest telescope William Optics has ever created—while featuring a 43.2mm image circle and the patented WIFD internal focusing system.
This ultra-fast optical system drastically reduces exposure times, helping capture faint nebulae, dark dust lanes, and expansive celestial structures in a fraction of the time. With its flat-field 7-element optics, stable internal focusing, and unique design that hints at technology from another world, the Mighty-Cat 71 Anniversary Edition is built for demanding deep-sky imaging with modern full-frame and cropped-sensor camera systems.
Mighty-Cat 71 Standout Features
Built-In Bahtinov Mask
Integrated bahtinov mask into the front cap for quick and accurate focusing, making precise star focus easier in the field.
Adventure Ready
Including a padded soft carrying case tailored specifically for the Mighty-Cat 71. Features precision-cut spacing to securely house the telescope with its heavy-duty mounting ring, handlebar, and dual-sided dovetail plate still attached.
Sensor Tilt Xterminator
Features a heavy-duty rear tilt and rotation interface designed to support modern imaging setups, reducing the chance of rear-end sag while retaining convenient sensor-squaring capability.
30th Anniversary Limited Edition Build
This special telescope was made to celebrate 30 years of William Optics designs. It uses high-quality metal parts that are precisely cut to fit together perfectly. Inside the telescope, a feature called Anti-Shrink Lens Cell Technology protects the glass. When you take photos outside on freezing cold nights, metals naturally shrink and expand, which can squeeze the telescope glass and blur your photos. This technology stops that from happening, keeping the glass perfectly lined up so your long-exposure photos stay sharp and clear all night.
7-Element Petzval Optical Design
The Mighty-Cat 71 features a fast f/3.2 focal ratio and 230mm focal length, making it the fastest optical system in the company's history. Its 7-element Advanced Petzval layout incorporates two Super ED glass elements, two Lanthanum elements, and three specialized X-elements to eliminate chromatic aberration. This design inherently corrects for field curvature, providing a flat 43.2mm full-frame image circle that delivers pin-sharp stars across large camera sensors without requiring a separate external field flattener.
Patented WIFD Focuser
For heavy camera loads, the telescope utilizes the patented WIFD (William Optics Internal Focuser Design) rack-and-pinion system. Shifting lens elements internally over a 0–35mm range instead of extending an external drawtube removes focus flexure, prevents sensor tilt, and eliminates mechanical vignetting. The ready-to-image package includes an integrated Sensor Tilt Xterminator (STX-R), an M54/M48 camera adapter stack, a patented multi-use handlebar for accessories, and a dual-sided Vixen/Arca-Swiss dovetail plate, all packaged in a custom-fitted protective soft carrying case.
Specifications
-
Optical Design: 7-Element Advanced Petzval
-
Lens Elements:
-
2x Super ED
-
2x Lanthanum
-
3x Special X-Glass components
-
-
Focal Length: 230 mm
-
Aperture: 71 mm (2.8 in)
-
Focal Ratio: f/3.2
-
Image Circle: 43.2 mm (Full-frame)
-
Focuser: WIFD Internal Rack & Pinion (ZWO EAF electronic focuser ready)
-
Focuser Travel: 0 mm to 35 mm (0 in to 1.38 in)
-
Adapters Included: Sensor Tilt Xterminator (STX-R) Rotator, M54 Camera Adapter, and M48 Camera Adapter
-
Optional Flattener: None required (Flat field is built directly into the 7-element Petzval design)
-
Camera Format Support: Full Frame, APS-C, and Micro 4/3 (M4/3)
-
T-Mount Support: Canon EF/RF, Nikon F/Z, Sony E, Pentax K, MFT (M4/3), and FUJI X
-
Dovetail Type: Reversible Vixen & Arca-Swiss
-
Optical Tube Length: 315 mm (12.4 in)
-
OTA Weight: 3.38 kg (7.45 lbs)
-
Total Weight: 4.1 kg (9.04 lbs) w/ included accessories
Diagram Reports
Wavelength Chart
Spot Diagram Chart
| Manufacturer | William Optics |
|---|---|
| Telescope Focal Length | Up to 300mm |
- 1x Mighty-Cat Refractor
- 1x Bahtinov Mask/ Front Cap
- 1x M48 Camera Adapter
- 1x M54 Camera Adapter
- 1x Dual-Side Dovetail Plate
- 1x Mounting Ring & Handle Bar
- 1x Allen Key Set
- 1x Soft Carrying Case
- 1x Commemorative Certificate
- 7-Element EVO Petzval w/ Super ED glass. No need to calculate back focus
- Built-in Sensor Tilt Xterminator w/ Rotator. Including M48 and M54 camera adapters
- Can support up to large full-frame camera sensors
- WIFD Rack & Pinion focuser - (EAF ready)
- Self-flattening design. No need for a separate field flattener
Limited Edition Mighty-Cat 71: Celebrate 30 Years of William Optics Excellence!
The William Optics Mighty-Cat 71 30 Years Anniversary Limited Edition is a 71mm astrograph engineered to redefine ultra-fast deep-sky imaging. Celebrating three decades of optical innovation, this exclusive 100-set limited run features a custom "Cosmic Visitor" design with intricate extraterrestrial modifications—a tribute to 30 years of peering into the unknown and chasing the mysteries of the universe. It introduces an unprecedented, record-breaking f/3.2 focal ratio—the fastest telescope William Optics has ever created—while featuring a 43.2mm image circle and the patented WIFD internal focusing system.
This ultra-fast optical system drastically reduces exposure times, helping capture faint nebulae, dark dust lanes, and expansive celestial structures in a fraction of the time. With its flat-field 7-element optics, stable internal focusing, and unique design that hints at technology from another world, the Mighty-Cat 71 Anniversary Edition is built for demanding deep-sky imaging with modern full-frame and cropped-sensor camera systems.
Mighty-Cat 71 Standout Features
Built-In Bahtinov Mask
Integrated bahtinov mask into the front cap for quick and accurate focusing, making precise star focus easier in the field.
Adventure Ready
Including a padded soft carrying case tailored specifically for the Mighty-Cat 71. Features precision-cut spacing to securely house the telescope with its heavy-duty mounting ring, handlebar, and dual-sided dovetail plate still attached.
Sensor Tilt Xterminator
Features a heavy-duty rear tilt and rotation interface designed to support modern imaging setups, reducing the chance of rear-end sag while retaining convenient sensor-squaring capability.
30th Anniversary Limited Edition Build
This special telescope was made to celebrate 30 years of William Optics designs. It uses high-quality metal parts that are precisely cut to fit together perfectly. Inside the telescope, a feature called Anti-Shrink Lens Cell Technology protects the glass. When you take photos outside on freezing cold nights, metals naturally shrink and expand, which can squeeze the telescope glass and blur your photos. This technology stops that from happening, keeping the glass perfectly lined up so your long-exposure photos stay sharp and clear all night.
7-Element Petzval Optical Design
The Mighty-Cat 71 features a fast f/3.2 focal ratio and 230mm focal length, making it the fastest optical system in the company's history. Its 7-element Advanced Petzval layout incorporates two Super ED glass elements, two Lanthanum elements, and three specialized X-elements to eliminate chromatic aberration. This design inherently corrects for field curvature, providing a flat 43.2mm full-frame image circle that delivers pin-sharp stars across large camera sensors without requiring a separate external field flattener.
Patented WIFD Focuser
For heavy camera loads, the telescope utilizes the patented WIFD (William Optics Internal Focuser Design) rack-and-pinion system. Shifting lens elements internally over a 0–35mm range instead of extending an external drawtube removes focus flexure, prevents sensor tilt, and eliminates mechanical vignetting. The ready-to-image package includes an integrated Sensor Tilt Xterminator (STX-R), an M54/M48 camera adapter stack, a patented multi-use handlebar for accessories, and a dual-sided Vixen/Arca-Swiss dovetail plate, all packaged in a custom-fitted protective soft carrying case.
Specifications
-
Optical Design: 7-Element Advanced Petzval
-
Lens Elements:
-
2x Super ED
-
2x Lanthanum
-
3x Special X-Glass components
-
-
Focal Length: 230 mm
-
Aperture: 71 mm (2.8 in)
-
Focal Ratio: f/3.2
-
Image Circle: 43.2 mm (Full-frame)
-
Focuser: WIFD Internal Rack & Pinion (ZWO EAF electronic focuser ready)
-
Focuser Travel: 0 mm to 35 mm (0 in to 1.38 in)
-
Adapters Included: Sensor Tilt Xterminator (STX-R) Rotator, M54 Camera Adapter, and M48 Camera Adapter
-
Optional Flattener: None required (Flat field is built directly into the 7-element Petzval design)
-
Camera Format Support: Full Frame, APS-C, and Micro 4/3 (M4/3)
-
T-Mount Support: Canon EF/RF, Nikon F/Z, Sony E, Pentax K, MFT (M4/3), and FUJI X
-
Dovetail Type: Reversible Vixen & Arca-Swiss
-
Optical Tube Length: 315 mm (12.4 in)
-
OTA Weight: 3.38 kg (7.45 lbs)
-
Total Weight: 4.1 kg (9.04 lbs) w/ included accessories
Diagram Reports
Wavelength Chart
Spot Diagram Chart
Other Information
- Country of Manufacture: Taiwan
| Manufacturer | William Optics |
|---|---|
| Telescope Focal Length | Up to 300mm |
- 1x Mighty-Cat Refractor
- 1x Bahtinov Mask/ Front Cap
- 1x M48 Camera Adapter
- 1x M54 Camera Adapter
- 1x Dual-Side Dovetail Plate
- 1x Mounting Ring & Handle Bar
- 1x Allen Key Set
- 1x Soft Carrying Case
- 1x Commemorative Certificate
William Optics Mighty-Cat 71 f/3.2 Limited Edition Refractor Telescope