What kind of mount is needed for the William Optics Mighty Cat 71?
With a total weight of 4.1 kg (9.04 lbs), the Mighty Cat 71 is very lightweight. Choose a compact equatorial or strain-wave mount whose imaging payload comfortably covers the telescope plus your camera, guide scope and accessories. The included dual-side plate fits both Vixen-style and Arca-Swiss saddles.
How critical is the 55mm +/- 3mm back spacing on the Mighty Cat 71?
William Optics designed the Petzval optics to work within a supported back spacing range rather than at one exact distance. As long as your complete camera setup stays within 55mm +/- 3mm, the focuser can reach focus normally. If the setup goes beyond this range, focus may no longer be achievable.
Can I use the William Optics Mighty Cat 71 for visual astronomy?
William Optics designed the Mighty Cat 71 as an astrograph for deep-sky imaging with cameras. It ships with camera adapters and a tilt and rotation interface rather than a diagonal or eyepiece holder, so it is intended for photographic use.
What makes the WIFD focuser on the Mighty Cat 71 special?
The WIFD (William Optics Internal Focuser Design) is a patented internal rack and pinion focuser with 0-35mm of travel, compatible with electronic auto-focusers. Keeping the focusing system centered inside the telescope improves balance and helps avoid rear drawtube flexure and vignetting.
How does the Mighty Cat 71's f/3.2 speed help with imaging the North American Nebula (NGC 7000)?
The North American Nebula is a large, faint emission nebula. The Mighty Cat 71's ultra-fast f/3.2 optics gather light much more rapidly than slower telescopes, allowing you to capture the faint, red hydrogen-alpha structures with significantly shorter exposure times. Additionally, its 230mm focal length is wide enough to frame the entire nebula, along with the adjacent Pelican Nebula (IC 5070), in a single shot on a full-frame camera.
Do I need a field flattener or reducer with the Mighty Cat 71?
No. The Mighty Cat 71 features a 7-element Petzval optical design that has field flattening built-in. It produces a flat 43.2mm image circle without the need for any external flattener or reducer, simplifying your imaging train.
What cameras are compatible with the Mighty Cat 71's M48 and M54 adapters?
The included M48 (2-inch filter thread) and M54 adapters make the Mighty Cat 71 compatible with nearly all modern astronomy cameras and DSLRs/mirrorless cameras. You will need the appropriate T-ring for your specific camera brand (e.g., Canon, Nikon, Sony) to connect to the M48 adapter to achieve the required 55mm back focus.
How do I focus the Mighty Cat 71 accurately in the field?
The Mighty Cat 71 includes a clever lens cap that doubles as a Bahtinov mask. Simply place the cap on the front of the telescope, point at a bright star, and adjust the WIFD focuser until the central diffraction spike is perfectly centered between the other two spikes. This is a fast and highly accurate method for achieving critical focus.
Is the 43.2mm image circle of the Mighty Cat 71 large enough for my full-frame camera?
Yes. A standard full-frame sensor has a diagonal of 43.2mm. The Mighty Cat 71's 43.2mm corrected image circle is designed to cover these sensors with a flat field, without an additional flattener.
How does the Mighty Cat 71 handle imaging galaxies like Andromeda (M31)?
The Mighty Cat 71 is exceptionally well-suited for the Andromeda Galaxy. M31 is famously large, over 3 degrees wide, and its faint outer spiral arms are difficult to capture. The 230mm focal length allows you to frame the entire galaxy with room to spare, while the f/3.2 speed helps bring out the faint dust lanes and outer extensions with much less total integration time.
What is the Sensor Tilt Xterminator (STX-R) on the Mighty Cat 71 used for?
The STX-R is a combination rotator and tilt adapter. The rotation lets you frame your target precisely without turning the entire telescope. The tilt adjustment allows you to make minute corrections to ensure your camera's sensor is perfectly perpendicular to the light path, which is crucial for achieving sharp stars across the entire flat field of a fast astrograph.
Is the William Optics Mighty Cat 71 suitable for travel?
Absolutely. With a tube length of only 315mm and an OTA weight of 3.38 kg, it is very compact and lightweight. Combined with the included soft carry case, it is an excellent choice for a high-end, portable imaging setup for travel to dark sky sites.
