Field Performance
The William Optics Gran Turismo 81 (GT81) has become a staple in the world of high-performance wide-field imaging. It features a triplet objective lens utilizing FPL-53 synthetic fluorite glass, which is widely considered the gold standard for color correction in refractors.
Mechanically, the scope is built like a tank. The 2.5" Rack & Pinion focuser is smooth, robust, and shows zero flex even when loaded with a heavy mono camera and filter wheel. One of its most distinctive quality of life features is the patented clear Bahtinov mask integrated into the lens cover.
Strengths
- Perfect color correction (Zero fringing)
- Patented built-in Bahtinov mask
- Rock-solid 2.5" R&P Focuser
- Top-tier aesthetic and mechanical finish
Considerations
- Backfocus is critical when using the Reducer
- Heavier than 80mm doublets or Petzvals
- Higher price point for the FPL-53 optics