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William Optics Cat 91 WIFD

Price:

849.000 KD


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William Optics Cat 91 WIFD

SKU WIL-T-C-91

Step up your astrophotography game with the William Optics RedCat 91, an advanced apochromatic refractor tailored for full-frame and medium-format cameras. This latest addition to the RedCat series combines portability with superior optical performance, making it a versatile tool for capturing breathtaking detail in deep-sky objects.

Highlights:

Petzval Design, No Backfocus Hassles
The 5-element Petzval design eliminates the need for backfocus adjustments, providing sharp, edge-to-edge images with pinpoint stars—ideal for wide-field and detailed astrophotography alike.

Full-Frame & Medium-Format Ready, No Extra Flattener Needed
With a large 55mm image circle, the RedCat 91 is perfect for both full-frame and medium-format cameras. Its advanced optics achieve flat-field images without requiring an additional flattener, giving astrophotographers the freedom to capture expansive views with unparalleled clarity.

Fast f/4.9 Focal Ratio
The RedCat 91's fast f/4.9 focal ratio is designed for bright, vivid captures of galaxies, nebulae, and beyond, ensuring excellent light-gathering power and sharp detail even on faint celestial objects.

Seamless WIFD Focusing
Equipped with William Optics' WIFD focuser, the RedCat 91 provides precise, stable focusing without additional adjustments, enhancing the ease of use for both seasoned astrophotographers and beginners.

The RedCat 91 blends the trusted RedCat heritage with William Optics’ innovative design, making it the ultimate choice for those ready to elevate their night-sky explorations.

849.000 KD 849.000 KD

  • Brand - William Optics
Lens Type
5-Element Advanced Petzval
Lens Elements
Super ED Glass x2 ED Glass x1 Lanthanum Glass x1 X-Element x1
Focal Length
448 mm
Diameter
91 mm
Focal Ratio
f/4.9
Image circle
55 mm
Focuser
WIFD R&P Focuser Compatible with EAF
Flange Distance
Maximum: M48 (60.8mm),M54 (65.8mm)
Focus travel
0-36 mm (Ruler to 40mm)
Adapter Included
Tilt Adjuster Rotator M63 → M54 Adapter M63 → M48 Adapter
Optional Flattener
No Flattener Required
T-Mount Support
Canon EF, RF Nikon F, Z Sony E Pentax K MFT (M4/3) FUJI X
Camera Format
Medium Format ( needs additional adapter ) Full Frame APS-C M4/3
Tube Length
556 mm
OTA Weight
4.72 kg / 10.41 lbs
Total Weight
6.3 kg / 13.89 lbs

Main Tube

Bahtinov Cap

M48 & M54 adapter

Mounting Plate

Mounting Ring Handle bar

Riser Blocks

Soft Carry Case

Brand William Optics
William Optics Cat 91 WIFD
William Optics Cat 91 WIFD
849.000 KD