Description

The Ultra-Cat 76 is a high-performance 76mm apochromatic refractor, designed for astrophotographers who demand exceptional clarity and true color accuracy.

With a 5-element advanced Petzval optical design, including super ED and lanthanum glass, and a fast f/4.8 focal ratio, this telescope delivers stunningly sharp, flat-field images across its 50mm image circle. Optimized for Full Frame, APS-C, and M4/3 sensors, it also offers compatibility with Medium Format cameras for outstanding wide-field astrophotography.

Key Features:

Advanced 5-Element Petzval Optics
Eliminates field curvature, ensuring sharp, edge-to-edge stars without additional flatteners.

50mm Large Image Circle
Fully supports Full Frame cameras, APS-C and M4/3 sensors for optimal performance. Compatible with Medium Format.

Fast f/4.8 Optics
Superior light-gathering capability, enabling deep-sky imaging with shorter exposure times.

WIFD (William’s Internal Focuser Design)
Patented internal rack-and-pinion focuser ensures stable and precise focusing.
No vignetting or balance issues — ideal for astrophotography.
Compatible with EAF (Electronic Automatic Focuser) for precision focus control.

Sensor Tilt Xterminator (STX) & Rotator
Integrated tilt adjuster eliminates sensor misalignment, ensuring uniform image sharpness.

No Flattener Required
The optical design naturally corrects field curvature, simplifying setup.

Anti-Shrink Lens Cell Technology
Reduces thermal expansion effects, maintaining perfect optical alignment in any climate.

Patented Bahtinov Mask for Focusing
Built-in focusing aid ensures pinpoint star sharpness with ease.

Premium Build & Ergonomic Design
Lightweight yet robust (4.31 kg / 9.5 lbs) construction with a sleek anodized finish.
Patented handle bar design for enhanced portability and ease of use.

Versatile Camera Compatibility
Supports Canon EF, RF, Nikon F,Z, Sony E, Pentax K, MFT, and FUJI X mounts.

Specifications

Lens Type	5-Element Advanced Petzval
Lens Elements	Super ED Glass x2 ED Glass x1 Lanthanum Glass x1 X-Element x1
Focal Length	365mm
Diameter	76mm
Focal Ratio	f/4.8
Image Circle	50mm
Focuser	WIFD R&P Focuser (Compatible with EAF)
Focus Travel	0-20mm (Ruler to 21mm)
Adapter Included	Sensor Tilt Xterminator Rotator M54, M48 Camera Adapters
Optional Flattener	No Flattener Required
T-Mount Suppot	Canon EF, RF Nikon F, Z Sony E Pentax K MFT (M4/3) FUJI X
Camera Format	Medium Format (Compatible) Full Frame (Recommended) APS-C M4/3
Tube Length	363mm-415mm
OTA Weight	3.81 kg / 8.4 lbs
Total Weight	4.98 kg / 10.98 lbs