William Optics Apochromatic refractor AP 81/478 Gran Turismo 81 IV OTA silver (67476)

The Gran Turismo refractor is an advanced apochromatic triplet telescope featuring an FPL-53 glass element for exceptional color correction, superior contrast, and sharp, high-resolution images. It is a versatile telescope that performs equally well for both visual observation and astrophotography, offering outstanding optical performance in a compact, travel-friendly design.

For visual observation
When equipped with an optional zenith mirror, the Gran Turismo delivers high-contrast views of the Moon and planets with remarkable color accuracy and detail. Its fast optics also make it ideal for observing deep-sky objects such as star clusters, galaxies, and nebulae. The crisp, pinpoint star images are particularly impressive when viewing or studying globular clusters, revealing fine details that are often missed in lesser instruments.

For astrophotography
The Gran Turismo is optimized for imaging when paired with the William Optics Flat6AIII flattener/reducer, which ensures a flat, evenly illuminated field across full-frame sensors. The integrated prism rail adapters in the carrying handle allow the attachment of a guide scope, which can function as both a finder and guiding system during long-exposure photography.

The 2.5-inch rack-and-pinion focuser provides smooth, precise focusing with dual-speed control (1:10 fine adjustment), an extended focusing range, and a built-in temperature display. An adapter for 1.25-inch eyepieces is also included, ensuring compatibility with a wide range of accessories.

Portable and robust design
The Gran Turismo apochromat is compact, durable, and ideal for mobile astronomy or travel. With a carrying length of just 390 mm and a solid build, it is easy to transport to dark-sky locations. Its stability and simplicity make it a perfect choice for advanced observers who value both optical quality and portability. Whether you’re exploring objects from the Messier or NGC catalogues, this telescope is a reliable companion for serious stargazing sessions.

Special feature: Bahtinov focus mask
Every Gran Turismo apochromat includes a specially designed Bahtinov focusing mask made of optical-grade acrylic glass with 92% light transmission. The laser-engraved diffraction pattern is approximately three times brighter than that of traditional metal masks, allowing more precise focusing—even on fainter stars—thanks to the clear and vivid diffraction spikes it produces.

The William Optics Gran Turismo Apochromatic Refractor combines precision optics, portability, and premium craftsmanship to deliver outstanding visual and photographic performance. With its advanced triplet design, robust mechanics, and elegant finish, it is an ideal choice for serious astronomers seeking both performance and reliability in a compact telescope.

Specifications

Optics

• Type: Refractor (Apochromat)

• Aperture: 81 mm

• Focal length: 478 mm

• Focal ratio: f/5.9

• Resolving capacity: 1.70 arcseconds

• Limiting magnitude: 11.3

• Light-gathering power: 130× (relative to the human eye)

• Maximum useful magnification: 162×

• Lens design: Triplet (FPL-53 element)

• Coating: SMC multi-coating

• Stray light baffles: Yes

Tube

• Tube weight: 3.9 kg

• Carrying length: 390 mm

• Tube length: 460 mm

• Color: Silver

Focuser

• Type: Rack and pinion

• Gear reduction: 1:10 fine focusing

• Free aperture: 64 mm

• Eyepiece connection: 2"

• Adapter: 2" / 1.25" included

• Motorized: No

• Thread (telescope side): M63

Mount

• Design: OTA (Optical Tube Assembly)

• Mounting type: None (optional mount required)

Included accessories

• Dew shield: Yes

• Finder scope: No

• Deviating optics: No

• Vixen-style prism rail: Yes

• Carrying handle: Yes

• Bahtinov focusing mask: Included

• Carry case: Included

Applications

• Astrophotography: Yes (excellent performance)

• Moon and planets: Yes

• Nebulae and galaxies: Yes

• Nature observation: No

• Solar observation: No (requires appropriate solar filter)

Recommended for

• Beginners: No

• Advanced users: Yes

• Observatories: No