William Optics BlackCat 91/448 APO WIFD OTA

BlackCat 91: the complete imaging execution

The William Optics BlackCat 91 WIFD is the most complete version in the Cat 91 class. The 91 mm Petzval optics with FPL53 and FPL51 glass deliver a color-pure, sharp image all the way to the edges of a full-frame sensor, and the included rotator and tilt flange provide complete control over composition and sensor alignment.

Everything for the perfect recording

With f/4.9 and a 448 mm focal length, you can photograph medium-sized nebulae and galaxies with short exposures. The rotator rotates the composition without touching the focus, the tilt flange corrects sensor tilt, and the M48 and M54 adapters connect virtually any camera train directly. The internal WIFD focuser supports all of that without sagging.

In the box

• Optical tube Cat 91/448 with WIFD focuser
• Rotator
• Candelabra
• M48 and M54 adapters
• Dovetail pliers
• Integrated Bahtinov mask
• Nylon tote bag

Featured accessories

A William Optics UniGuide 50mm Guidescope (from 189 euros) is the fitting guide for this class. The M48 and M54 connectors directly accept common William Optics camera adapters.

For whom yes, for whom no

Pros: advanced astrophotographers who want maximum control over composition and sensor alignment, in the black version. Cons: those looking for the same optics without a rotator and tilt adapter; the RedCat 91 WIFD is the more simply equipped choice in that case.

Specifications

Unsure about the right tube for your camera and mount? The telescope selection aid helps you choose. Also view all Refracting telescopes and the full range of William Optics.