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SKU: T-C-131BR

Ultra-Cat 131

Sale price$5,398.00 USD Tax excluded.
⛟ Free Shipping Free shipping on orders over $498. Import charges not included.
Description
Description

The William Optics Ultra-Cat 131 is the flagship of the Ultra-Cat series, representing the pinnacle of wide-field astrophotography performance. Built around a large-aperture 131mm apochromatic optical system and an advanced 5-element Petzval design, it delivers extraordinary light-gathering power, exceptional color correction, and razor-sharp stars across an expansive, flat image circle.

Designed for serious astrophotographers and observatories alike, the Ultra-Cat 131 combines a fast focal ratio with uncompromising optical precision, enabling stunning deep-sky detail, rich contrast, and immersive wide-field compositions. Its premium mechanical construction, thermal stability, and flagship-level engineering set a new benchmark for large-format astrophotography systems.

Key Features:

Advanced 5-Element Petzval Design
Eliminates field curvature, providing sharp, flat-field images without requiring additional flatteners.

60mm Superior Image Circle
Fully supports full-frame and medium-format cameras for wide-field and detailed astrophotography, outperforming standard 106mm telescopes.

F/4.9 Fast Optics
Offers exceptional light-gathering capability for vibrant deep-sky photography.

WIFD (William’s Internal Focuser Design)
Patented internal focuser ensures precise, stable, and hassle-free imaging, avoiding balance issues and eliminating vignetting.

Anti-Shrink Lens Cell Technology
Minimizes thermal expansion and contraction, maintaining perfect optical alignment in any environment.

Sensor Tilt Xterminator
Integrated and patented design eliminates distortion, optimizing sharpness and detail for professional-level results.

Built-In Patented Bahtinov Mask
Simplifies focusing for pinpoint precision, a feature that sets it apart from competitors.

Patented Handle Bar Design
Combines ergonomic usability with enhanced portability.

Personalized Laser Engraving
Free customization for direct purchases, adding a personal touch to your telescope.

Notice
Notice

Astrophotography Only
This telescope is specifically designed for astrophotography, and its optical design does not support visual observation.

Color:Ultra
  • The next batch will be ready in August
Ultra-Cat 131
Ultra-Cat 131 Sale price$5,398.00 USD Tax excluded.

What's in the box

Main Tube

Bahtinov Cap

M48, M54, M68
Camera Adapter

Losmandy Plate

Mounting Ring & Handle bar

Soft Carry Case

Allen Key Set

Powering the Grandest Deep-Sky Visions

The Ultra-Cat 131 stands as the flagship of the series, redefining wide-field imaging performance. Built on an uncompromising 5-element Petzval optical system, it delivers exceptional flat-field precision, color fidelity, and light-gathering power. Purpose-engineered for advanced astrophotographers, the Ultra-Cat 131 turns ambitious deep-sky visions into true-to-life celestial images with confidence and control.


Advanced Petzval

Researched and developed by WO, the innovative 5-element Petzval design redefines telescope optics. This advanced system achieves a flawless spot diagram across a medium-format image circle.

Extra-low Dispersion (ED) glasses

Contains 2 Super ED, 1 ED glasses and lanthanum lenses with advanced fully multi-coated, delivering sharp, vibrant images with true-to-life colors, significantly reducing chromatic aberration.

Needs NO Flattener

The Petzval design inherently flattens the field, eliminating the need for an external field flattener.

Never easier to capture deep sky objects

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Comprehensive Configuration

Precision Imaging Adjustment

Sensor Tilt Xterminator (STX-R)

Evolved from the original STX system, the STX-R introduces a reversed rear mechanical layout for improved support under heavier camera setups, while preserving convenient side-access tilt adjustment.

Camera Angle Rotator

Adjust camera orientation with precision and confidence, giving you better framing control without compromising rear-end mechanical stability.

Compatible with Electronic Motorized Devices

Hassle Free Installation
( No Mounting Bracket Kit required )

Leading the market

Wo patented design

The Ultra-Cat 131 holds three unique patents, ensuring easy and perfect focusing along with precise coaxial image quality, preventing draw tube tilt issues caused by optical misalignment.

:

Internal Focuser

The WIFD focusing design relocates the focuser to the center of the telescope, eliminating tube tilt caused by the weight of cameras and accessories. By removing the need for a traditional rear drawtube, the optical path remains fully unobstructed, ensuring clean and precise image performance.

Integrated Bahtinov mask

Laser engraved on high-definition and stable optical PMMA. Enhances astrophotography experience with quick and accurate adjustments.

CAT Handle Bar

Crafts for enhanced portability and versatility.

Mounting Ring

Designed for seamless functionality without compromising on stability. Engineered with wide surface contacts, this innovative ring ensures a secure fit while enabling fast, easy detachment.