William Optics RedCat 61 / 300 mm f/4,9 APO.

William Optics RedCat 61 / 300 mm f/4,9 APO.

This latest introduction to the popular RedCat family features 61mm Petzval optics, a fast f/4.9 focal ratio, and William Optics' new WIFD dual-speed internal focusing mechanism for zero drawtube flexure.

The fully multicoated Petzval optics include two synthetic fluoride (FPL53 and FPL51) ED glass elements that deliver a full-frame, flat-field image with negligible chromatic aberration.

The new WIFD internal focusing mechanism eliminates flexure on the drawtube and is compatible with the ZWO EAF.

With its compact size and fast f/4.9 focal ratio, the RedCat 61 is an excellent choice for convenient wide-field astrophotography or piggybacking. 

Other features include a field rotator, a slot for 48mm filters, a reversible dovetail for either Vixen-style or Arca-Swiss mounting and a Cat Handle with a saddle that accepts William Optics Uniguide/Slide Base Guidescopes.

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Key Features

• High-Quality Petzval 4-Element Optics with FPL-53 & FPL-51 ED glass, delivering a full-frame, flat-field image with minimal chromatic aberration.
• Fast f/4.9 Focal Ratio – Ideal for capturing deep-sky images with stunning wide-field clarity.
• WIFD Internal Focuser – Ensures tilt-free focusing, eliminating flexure and backlash, with direct ZWO EAF compatibility for seamless motorized autofocus.
• Compact & Lightweight Design – Perfect for portable setups and piggyback mounting on larger telescopes.
• Built-in 48mm Filter Slot – Easily integrate 2" filters for advanced imaging.
• Integrated Field Rotator – Precisely adjust your framing for optimal composition.
• Universal Mounting System – Reversible dovetail for both Vixen-Style & Arca-Swiss compatibility.
• Cat Handle with Guide Scope Saddle – Directly mount a William Optics Uniguide/Slide Base Guide Scope.

What's in the Box?

• RedCat 61 WIFD Refractor with internal focusing system
• Bahtinov Mask integrated into the dust cap
• Removable Dew Shield
• Cat Handle with accessory saddle
• Built-in Field Rotator
• 48mm Filter Slot
• Reversible Vixen-Style / Arca-Swiss Dovetail Mount

Technical Specifications

• Optical Design: 4-Element Petzval
• Glass Type: FPL-53 / FPL-51
• Aperture: 61mm
• Focal Length: 300mm
• Focal Ratio: f/4.9
• Image Circle: 45mm (Full-Frame)
• Focuser: William Optics Internal Focus Design (WIFD)
• Focuser Compatibility: ZWO EAF
• Mounting System: Vixen-Style & Arca-Swiss
• Weight: Ultra-portable and optimized for lightweight mounts

Why Choose the RedCat 61 WIFD?

• Exceptional optical performance with full-frame, flat-field imaging
• Hassle-free focusing with an internal tilt-free focuser
• Portable & versatile – Ideal for mobile astrophotography & piggyback setups
• Direct compatibility with ZWO EAF and 48mm filters