William Optics Might-Cat71

William Optics Might-Cat71

The fast William Petzval astrograph MightyCat 71 is ideal for imaging faint nebulae, dark dust lanes, and expansive celestial structures.

  • Aperture 71 mm / focal length 230 mm / focal ratio f/3.2
  • Captures large areas
  • Short exposure time even with low-light subjects
  • Modified Petzval design with two ED and two lanthanum glass elements - a seven-element lens!
  • Very well-corrected image field with a diameter of 43.2 mm - also suitable for full-frame cameras
  • Focusing via internal focusing (William Internal Focus Design - WIFD) as found in telephoto lenses, compatible with EAF
  • Correct working distance automatically achieved when the image is in focus
  • Tilting function for individual adjustment of the camera sensor to the telescope
  • 360° camera rotation for the correct image framing
  • Camera mount via M54 or M48 external thread - working distance approximately 55 mm
  • Flexible dovetail bar at the base, compatible with Vixen saddle plates and Arca-Swiss quick-release systems
  • Bahtinov mask for astrophotography included
  • Tube length only 315 mm / weight with tube ring and dovetail 4.1 kg - suitable for travel
Manufacturer : William Optics
SKU : WiO-T-MC-71RD
Price: 2598.00 € incl tax 19% (Germany)
Estimated delivery time : 1-3 weeks (valid for new orders)
Product description

The William Optics Mighty-Cat 71 is a groundbreaking 71mm apochromatic astrograph designed for astrophotographers who need ultra-fast wide-field performance with maximum light-gathering efficiency. Built on an 7-element EVO Petzval optical platform, 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.

The ultra-fast f/3.2 optical system drastically reduces required 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 unmatched optical speed, the Mighty-Cat 71 is built for demanding deep-sky imaging with modern full-frame and cropped-sensor camera systems.

Key Features:

F/3.2 Ultra-Fast Optics
Captures deep-sky objects with unparalleled efficiency, utilizing the fastest optical system in William Optics history to maximize photon collection and shorten exposure tracks.

7-Element EVO Petzval Design
Provides a naturally flat image field without requiring an additional field flattener, delivering sharp stars and clean detail across a wide imaging area.

43.2mm Full-Frame Image Circle
Supports full-frame, APS-C, and M4/3 camera systems, giving astrophotographers total freedom for wide-field composition and high-resolution deep-sky imaging.

WIFD (William Optics Internal Focuser Design)
The patented internal focusing system keeps the focusing mechanism centered inside the telescope, improving balance and helping avoid rear drawtube-related flexure or vignetting.

Sensor Tilt Xterminator (STX-R)
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.

Anti-Shrink Lens Cell Technology
Helps maintain stable optical alignment under changing temperatures by minimizing the effects of material expansion and contraction around the lens cell.

Built-In Patented Bahtinov Mask
Integrated into the front cap for quick and accurate focusing, making precise star focus easier in the field.

Patented Handle Bar Design
Improves handling, portability, and accessory mounting while maintaining the clean mechanical layout of the Mighty Cat platform.

Personalized Laser Engraving
Available for direct purchases, allowing each telescope to carry a customized personal mark.

Scope of Delivery:

  • See picture

Products specifications
Technical Data
Lens type:7-element EVO Petzval lens
Lens elements:Super ED glass x3, other glasses x4 (including lanthanum glass)
Focal length:230 mm
Aperture:71 mm
Focal ratio:f/3.2
Image circle:43.2 mm
Focuser:WIFD R&P focuser with 1/10 speed reduction, compatible with EAF
Focuser travel:0-35 mm
Adapters included:"Sensor Tilt Xterminator" (STX-R) tilt flange, rotator, M54 threaded adapter, M48 threaded adapter
Optional flattener:No flattener required
T-mount support:Canon EF, RF, Nikon F, Sony E, Pentax K, Fuji X, Micro Four Thirds
Camera formats:Full-frame, APS-C, Micro Four Thirds
Dovetail bar type:Vixen, Arca-Swiss
Dovetail bar length:210 mm
Tube length:315 mm
OTA weight:3.38 kg / 7.45 lbs
Total weight:4.1 kg / 9.04 lbs