William Optics MiniCat 51 WIFD f/3.5 Petzval Refractor Telescope - Red

William Optics MiniCat 51: the Perfect Wide-Field Astrophotography Telescope

Building on the massive success of the RedCat 51 series, William Optics has now introduced the MiniCat 51! Weighing in at  just 5 lbs (2.3 kg) and featuring a small footprint with a full frame image circle, this tiny scope is designed for producing jaw-dropping wide-field astrophotography images.

Gather Light Twice as Fast as the RedCat 51

The RedCat 51 series has kept one thing constant: the f/4.9 focal ratio. This all changes with the MiniCat 51. It now features a blazing fast f/3.5 focal ratio, meaning it can gather the same amount of light in less than half the time as the RedCat 51!

This faster focal ratio lets you focus more on capturing your target in staggering detail. Of course with the focal ratio change also comes a change in focal length: the focal length is reduced from 250mm down to 178mm. This focal length is ideal for capturing large widefield views of the night sky.

Same Full Frame Image Circle

Despite a faster focal ratio, the MiniCat 51 retains its 43mm image circle from the RedCat 51. William Optics was able to achieve this by using 6 elements for this scope instead of 4, with two of them being super ED elements in the familiar Petzval design. As usual, William Optics has spared no quality components even in the smallest scope they've ever produced.

WIFD Focuser: Ideal for Serious Imaging

Like many telescopes William Optics has produced recently, the MiniCat 51 features the same patented WIFD focuser design. This design moves all lens elements internally to achieve focus, meaning there is no drawtube to rack in or out — great for retaining a small profile travel scope. The WIFD focuser is compatible with the ZWO EAF and other popular autofocus designs out of the box, which is a welcome feature on a scope this small.

Many widefield imagers have had to resort to using camera lenses like the Rokinon 135mm (also known as the Samyang 135mm) which have a helical focuser. This makes using an autofocus mechanism difficult and costly as you have to buy adapters and piece it together. The MiniCat 51's design makes it super easy to say goodbye to fussing with third-party autofocus kits.

Rotator, Dovetail Bar, & Saddle Handle Included

The MiniCat 51 comes standard with a number of accessories to make imaging a breeze. It comes with a Vixen-style dovetail bar, tube rings, a CAT series carrying handle with mount for a guide scope on top, and a marked 360-degree rotator on the back to allow you to dial in the perfect framing.

William Optics MiniCat 51 Specifications:

• Lens Type: 6-Element Petzval Design
• Focal Length: 178 mm
• Diameter: 51 mm
• Aperture: f/3.5
• Image circle: 43.2 mm
• Focuser: WIFD R&P Focuser, Compatible with EAF
• Adapter Included: Tilt Adjuster, Rotator, M54 → M48 Adapter
• Optional Flattener: No Flattener Required
• Camera Format: Full Frame (Compatible), APS-C (Recommended), M4/3
• Tube Length: 210 mm
• OTA Weight: 1.67 kg / 3.68 lbs
• Total Weight: 2.29 kg / 5.05 lbs