WILLIAM OPTICS GRAN TURISMO 81 WIFD
William Optics Gran Turismo 81 – A Game Changer with Patented Internal Focus Design (WIFD)
With the patented Internal Focus Design (WIFD), the William Optics Gran Turismo 81 transforms the game. This apochromatic triplet refractor features a unique focuser mechanism that is housed inside the tube, resulting in improved stability when cameras and accessories are attached. This innovative design virtually eliminates vignetting, ensuring your images remain uncompromised.
The Gran Turismo 81 offers an 81?mm aperture and employs a triplet optical configuration. Its apochromatic optics, crafted from FPL?53 glass, deliver crisp, high?contrast, and sharp images free of chromatic aberration. With a focal length of 478?mm, the telescope achieves a fast focal ratio of f/5.9.
In addition, the package includes the William Optics Flat6AIII field flattener/reducer, which provides a 0.8× reduction, and the William Optics 32?mm UniGuide Finder Scope. The finder, with a focal length of 120?mm and an f/3.75 ratio, mounts onto the GT81’s handle for added convenience.
A Technically Capable and Stylish Astrograph
Along with its patented internal focuser, the Gran Turismo 81 integrates numerous high?quality components and accessories. The red accents add a stylish touch to the scope. Its triplet design ensures high?performance optics, and the included Bahtinov mask helps achieve precise focus. Versatile tube rings with an integrated handle not only make carrying the tube effortless but also serve as a mounting point for small accessories like a finder scope. In summary, the William Optics Gran Turismo 81 is a sophisticated, capable, and innovative astrograph.
Introducing the William Optics Internal Focus Design (WIFD)
The new WIFD features a patented center focuser that moves fixed optical elements internally to prevent image shift. An integrated position viewing window displays the numerical focus setting instantly. Its smooth rack?and?pinion mechanism delivers ultra?fine focus adjustments. Protected within the tube, the internal moving optics stay in alignment, while the improved weight distribution enhances balance during imaging sessions.
Outstanding Optics
The Gran Turismo 81 boasts excellent optics. Its triplet refractor assembly utilizes premium FPL?53 apochromatic glass to minimize chromatic aberration and achieve superb contrast, color correction, and sharpness. The unique internal focuser slides otherwise fixed optics, preventing image shift and virtually eliminating vignetting.
Included Reducer/Flattener
Also included is the William Optics 2" Field Flattener/Reducer, designed to optimize flat?field performance of the GT81. The Flat6AIII, built with Ohara glass and fully multi?coated, provides uniform illumination across 97% of full?frame sensors with a reduction factor of 0.8×. Designed with M63 threads on the telescope side, this flattener/reducer threads directly into the scope. Its opposite side features 2" threads to accept a 48?mm (Wide) T?ring for your DSLR, plus a slot behind the threads to accommodate an M48 filter.
Included Slide?Base 32?mm UniGuide Finder Scope
The package includes a 32?mm UniGuide finder scope featuring a 120?mm focal length and an f/3.75 ratio, which mounts into the GT81’s handle. The back of the UniGuide is threaded with an M42 connection, allowing for attachment of 1.25" cylindrical guide cameras from brands like QHY, SBIG, and ZWO. Secure tightening knobs ensure a stable fit for your guiding setup.
Additional Accessories
The Gran Turismo 81 WIFD comes with several accessories to enhance performance and ease of use. In addition to the flattener/reducer, UniGuide finder scope, and the internal focuser, the package includes a Rotolock field rotator that facilitates precise camera orientation. A Bahtinov mask assists with focusing, and the optical tube rings with dovetail enable easy mounting. The integrated handle doubles as an accessory shoe, and a soft carrying case is provided for effortless transport
REVIEW of WILLIAM OPTICS GRAN TURISMO 81 WIFD 👇
