William Optics AP 81/478 Gran Turismo 81 IV OTA Apochromatic refractor

The Gran Turismo refracting telescope boasts an apochromatic triplet design with an FPL-53 element, ensuring exceptional color purity and high contrast. This versatile telescope is a comprehensive solution for various astronomical pursuits.

For visual observation, you can enhance your experience with an optional zenith mirror, delivering unparalleled contrast for viewing the Moon and planets with remarkable clarity. The high-speed apochromat facilitates extended exploration of challenging Deep Sky objects, including star clusters, galaxies, and nebulae, thanks to its sharp star representations, particularly ideal for observing and analyzing globular clusters.

For astrophotography enthusiasts, we recommend pairing the Gran Turismo with William Optics’ Flat6AIII flattener and reducer, providing an even field and consistent focal position for full-frame cameras. With integrated prism rail adapters on the handles, you can easily mount a guiding scope for precise tracking, serving as both a finderscope and guide sleeve.

The Gran Turismo features a robust 2.5” R&P focuser with a long focusing path, reduction capability, and temperature display. An adapter for 1.25” eyepieces is included for added versatility.

This telescope is ideal for travel and mobile astronomy and astrophotography, allowing you to journey beneath dark skies and explore the best objects from the Messier and NGC catalogues. With its straightforward setup, stability, and exceptional performance, the Gran Turismo will quickly become your favorite telescope, from the very first light!

One notable feature of William Optics’ new apochromats is the specially calculated Bahtinov focus mask, crafted from optical acrylic glass with 92% transparency. The imprinted diffraction pattern offers three times brighter visibility compared to traditional metal masks, ensuring clearer focusing even with fainter stars.

Included accessories

• Finder scope: No
• Dew Shield: Yes
• Deviating optics: No
• Eyepiece adaptor: 1.25" - 2"
• Prism rail: Vixen-Style
• Miscellaneous: Bahtinov focus mask
• Carrying handle: Yes
• Carry case: Yes

SPECIFICATIONS

Optics

Type: Refractor

Type of build: Apochromat

Aperture (mm): 81

Focal length (mm): 478

Aperture ratio (f/): 5.9

Resolving capacity: 1.70

Limit value (mag): 11.3

Light gathering capacity: 130

Max. useful magnification: 162

Tube weight (kg): 3.9

Carrying length (mm): 390

Tube length (mm): 460

Coating: SMC multi-coating

Stray light baffles in the OTA: Yes

Lens design: Triplet

Focuser

Type of build: Gear rack

Connection (to eyepiece): 2

Free aperture (mm): 64

Motorized: No

Ring clamp: Yes

Gear reduction: 1:10 Fine movement

Connecting thread (telescope side): M63

Mount

Type of build: OTA

Mounting type: No mount

General

Series: Gran Turismo

Colour: Gold

Area of application

Astrophotography: Yes (very good)

Moon & Planets: Yes

Nature Observation: No

Nebulae & galaxies: Yes

Sun: No (Only with appropriate Sun filter)

Recommended for

Beginners: No

Advanced: Yes

Observatories: No