William Optics

Gran Turismo 81 f/5.9 Triplet APO


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  • Regular price $1,538.00

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Innovative Bahtinov Mask Cover (Patented) & DSD Dovetail Plate included

The new 2020 GT81 three-element super APO Anniversary offer superb quality for imaging and visual use at an affordable price!From the pristine white finish on the CNC to the elegant gold trim which has more than just good looks...

Optically Unbeatable

  • Triplet air-spaced objective (FPL-53) in adjustable CNC machined ultra high precision lens cell.
  • Extremely sharp.
  • Excellent color correction.
  • Each lens is Fully Multi-Coated with a special super-high transmission coating (STM Coating) on all surfaces.
  • This F/5.9 lens is ideal for astrophotography.
  • NEW integrated Camera Rotator

2.5”R&P Focuser

2.5”R&P Ultra robust focuser with 1:10 dual speed: a treat to use during astrophotography. No image shifting! Heavy duty: perfect for your accessories.

Simply Beautiful Finish

Pure William Optics quality fit and finish: powder-painted white CNC-machined aluminum tube, with Gold, Red, or Space Grey trim finish, retractable dewshield, and dewshield cap.

Top quality anodizing.

Very compact for carrying on flights.

Attention to Details

2" & 1.25" adapter included in the price.

Anti-marring brass compression rings.

Though you will never need it, you have a 2-year warranty from WO, and the certainty that we will be there to assist you even beyond that, if you need!


    81 mm (3.25")

    Focal Length

    480 mm

    Focal Ratio


    Glass Type


    Optical Design


    Tube Weight

    9 lbs

    Tube Length (retracted)


    Dew Shield Outer Diameter (for Solar Filter) 103mm
    • Mounting Rings
    • CNC Carry Handle Bar
    • Dovetail Plate
    • 2.5” R&P Focuser with 2" and 1.25" adapters.
    • Innovative Bahtinov Mask Cover (Patented)
    • Soft Carry Case


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