William Optics has added to their family of Cat telescopes with a new, mini, addition.  The Cat 51 is has been made shorter, faster and wider.   Weighing in at just 5 pounds (2.3 kg), with a focal length of 178mm, you'll get the same high quality optics, internal focusing system, and accessory compatibility that you expect from a SpaceCat refractor.  The ultra compact body is just 210mm long (just over 8.25") making this an idea option for travel. 

Regardless of the shortened focal length, the SpaceCat mini maintains the same 43mm image circle that the longer focal length Cat 51 has.  To do this, William Optics added two additional lens elements making this a 6 element refractor design that includes two ED Petzval elements.   The shortened focal length allows users to capture images faster, allowing you to get more exposures in during your imaging session. 

William Optics' MiniCat 51 telescope features their patented WIFD focuser system, which offers a significant improvement over traditional refractor focusers. Unlike conventional designs that extend and collapse a tube outside the main telescope, potentially causing tilt and vignetting, the WIFD system adjusts focus by moving the optics inside the telescope. This design ensures a stable, tilt-free connection and allows the full light cone to pass through, preserving image quality.

The MiniCat 51’s WIFD focuser is compatible with electronic autofocus systems like the ZWO EAF, simplifying the process and eliminating the need for third-party autofocus kits. For manual focus enthusiasts, it also includes a dual-speed focus knob and an analog thermometer-equipped coarse focus knob, making it a versatile and user-friendly option for both automated and manual focusing.

Typically made with 4 optical elements, the Minicat adds two Super ED additional elements to create a 6 element Petzval design.   Favored by astroimagers for crystal clear images with little to no abberation, the Petzval design is known for its ability to produce a flat field, which minimizes field curvature.  With a flat field, the fine details of astronomical objects, such as galaxies, nebulae, and star clusters, are captured more accurately across the entire frame. The result is higher-quality images with better resolution and contrast.  William Optics has mastered refined Petzval designs and has managed to take it to the next level by downsizing an already compact refractor design.   The MiniCat body is a full 88mm (nearly 3.5") shorter than the travel friendly f/4.9 Cat 51.  

Ready to start imaging, just add t-ring!  The MiniCat is compatible with Canon EF and RF,  Nikon F and Z, Sony E, Pentax K, MFT (M4/3), and FUJI X t-rings.  It is full frame sensor compatible and designed for APS-C sensors as the recommended sensor size as well as M43.

Features like the clear index markings on the rotator, easy to reach and turn knobs, and a handle bar make using the Minicat a comfortable and intuitive experience.   William Optics also includes everything you need to start using the telescope, right out of the box: a V series dovetail and tube ring, a handle that doubles as a top mount bracket for accessories like a guidescope or remote control hub, and an included Bahtinov mask to fine tune your focus tucked into the front dust cap.    The only thing you will not find included is the built in filter drawer.  Ready to accept the same range of accessories as it's larger counterpart, the Minicat is easy to pack, grab and go. 

While slightly heavier than the f/4.9 version due to the additional lens elements, this compact refractor is just 5.05lbs and only 210mm long.  Paired with a travel-friendly tracking mount, you could easily bring this system along with you in a carry on bag on a flight or have a condensed and lightweight system to take out to your favorite dark sky locations.