NEW William Optics RedCat 71 WIFD APO 350mm f/4.9 - T-C-71RDII

William OpticsSKU: T-C-71RDII

Sale price$2,427 CAD
Only 1 unit left

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The wildly popular William Optics RedCat has earned it's place as a legendary astrograph. These use premium glass to deliver accurate color, a flat image, and a wide field. They're great little scopes, perfect for imaging massive nebulae like the flame and horsehead in Orion's belt.

Petzval's are the original fast, wide lenses. They were mathematically designed optics that were way ahead of their time when first developed in the 1840's (that's not a typo) and they are still relevant today. They're known for being flat to the edges, so you won't get any bloated or stretched stars in the corners of your images. They're also super-wide, so you can use a massive camera sensor and take in vast swaths of the night sky.

The RedCat is an advanced astrograph that takes advantage of premium modern glass, and cutting-edge camera technologies to take your astrophotography to the next level.

RedCat 71 Optical Design

The William Optics RedCat 71 is the bigger brother to the highly-regarded RedCat 51, which has been raved about by astrophotographers since its release. Building on the RedCat 51's success, the RedCat 71 keeps the same f/4.9 focal ratio and Petzval optical design. This optical design uses four lens elements instead of the three found in triplet refractors. By incorporating this extra element, the RedCat 71 is able to achieve a flat field without the need for an additional field flattener.

RedCat 71 Image Circle & Camera Compatibility

The flat field image circle on the WO RedCat 71 is over 45mm in diameter, meaning it can provide round stars to the corners on a full frame camera, not something many telescopes can claim in this price range. The RedCat 71 telescope comes with a 48mm thread on the back, meaning you can easily attach any dedicated astronomy camera with a standard M48x0.75 connection such as ZWO. For DSLR and mirrorless users, simply add an M48 t-ring for your camera type and you'll be ready to do astrophotography right out of the box.

Game-Changing WIFD Focuser

New in the third generation of the RedCat 71, this telescope features William Optics' new patented WIFD focuser. This game-changing design allows the telescope to focus by moving lens elements internally instead of externally. This has numerous benefits, including reducing vignetting, focuser sag, and most importantly, sensor tilt. The WIFD focuser is also compatible with the ZWO EAF out of the box, unlike previous versions of the RedCat 71.

SKU Number
Model Number
Telescope Series
William Optics Cat
Focal Ratio
Optical Design
Telescope Aperture
71mm (2.8")
Telescope Mount Type
No Mount - OTA Only
Type of Electronics
OTA Only - No Electronics
Number of Refractor Elements
4 (Quad)
Focal Length (mm)
348 mm
Image Circle
45 mm (Full Frame)
Focuser Style
William Optics WIFD
Focuser Speed
Dual Speed
Refractor Dew Shield Diameter (in.)
4.1" (105 mm)
Telescope OTA Weight (lb.)
9.47 lbs

William Optics - 2 Years

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