William Optics GT-71 II 2019 - Checked & Tuned
William Optics GT-71 II 2019 - Checked & TunedWilliam Optics GT-71 II 2019 - Checked & TunedWilliam Optics GT-71 II 2019 - Checked & Tuned
William Optics GT-71 II 2019 - Checked & TunedWilliam Optics GT-71 II 2019 - Checked & TunedWilliam Optics GT-71 II 2019 - Checked & Tuned

William Optics GT-71 II 2019 - Checked & Tuned

  (5 Reviews)
✓ 2 year warranty


4x in stock shipped 1-2 working days

About this product

Model:  wo_gt71_ii_rd
Part Number:  A-F71GTIIIRD

Optical Bench Test

FLO tests all William Optics triplet refractor telescopes before dispatch. 

You can be confident your telescope will, from the outset, have well figured optics, negligible false colour and spherical aberration, and no astigmatism (the bane of any optical system!).

Star shapes will be round, not triangular, oval or egg-shaped!

New 2019 GT-71 II Telescope - Price includes a pre-dispatch optical bench test. 

The William Optics GT-71 APO Triplet refractor features a 3-element f/5.9 objective with an Ohara FPL-53 extra-low-dispersion glass element for optimum colour correction and a new upgraded dual-speed 2.5-inch Rack and Pinion focuser with 1:10 Dual Speed. 

The William Optics 0.8x focal reducer is also available to reduce the focal-ratio to a fast f4.72. 

An excellent choice for astrophotography!

Includes tube rings, carry handle/guider mounting saddle.


    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 ultra robust 2.5" Rack and Pinion focuser with 1:10 dual speed: a treat to use during astrophotography. No image shifting.
  • Comes with two locking screws on angled positions for heavy load applications.
  • Graduated scale for precise camera alignment.

    Simply Beautiful Finish

  • Pure William Optics quality fit and finish: powder-painted white CNC-machined Aluminium tube,  gold trim finish, retractable dewshield, dewshield cap with patented Bahtinov mask.
  • Top quality anodising.
  • Very compact for carrying on flights.

What's in the box

  • Telescope OTA
  • Vixen compatible dovetail plate/li>
  • Carry Handle
  • Bahtinov Mask
  • Soft Carry Bag


Aperture 71mm
Focal Ratio F/5.9
Focal Length 420mm
Resolving Power 1.62
Limiting Magnitude 11.1
Objective Type Three element with FPL-53 Air Spaced
Lens Shade Retractable
2.5" Rack and Pinion Focuser 1:10 fine focus


1.25" Adapter
Field Stops Baffles
Type of Mount Includes mounting rings and Vixen style dovetail
Tube Diameter 82mm (dew shield tube 92mm)
Tube Length

390mm Fully Retracted

Tube Weight 2.95kg

Customer reviews

Average Rating (5 Reviews):  
Write a Review and share your opinions!

Rating (max 5):  
10 out of 10
09 December 2022  | 

I recently received my William optics GT71, I haven't had chance to use it yet because of the obvious (UK weather) what I can say is the build quality of the scope is amazing, I upgraded from a doublet which I was getting brilliant images with so quite looking forward to see what this triplet can do, I researched this scope and not heard a bad thing about it, i also purchased the matching flattener/reducer and 50 guide scope, thanks to the team at FLO for brilliant advice and fast delivery, 10/10 for product and service

Rating (max 5):  
Beautifully Made OTA
26 April 2022  | 

I decided to buy the William Optics GT-71 II as my widefield Astro Scope, having previously owned a Redcat 51. The telescope is beautifully made and just oozes quality. Iíve used it on one night so far, with a WO Field Flattener/Reducer and it produces beautiful images. Some things to considerÖ the OTA has no camera rotator so unless you buy one then framing will be tricky. You also need the Field Flattener/Reducer to get good stars to the edge, depending on your sensor sizeÖ Iím using an APS-C and have some slightly dodgy stars at the edge due to tilt in my optical train that Iím sorting out. The scope is also quite back-heavy with an EFW and Astro Camera so a larger dovetail might be required, Iím using the 400mm WO Losmandy and it easily solves this issue. Overall, I love the GT71, it does require further investment to get it up and running as a user-friendly rig but itís well worth every penny.

Rating (max 5):  
Fantastic telescope, feels beautiful!
30 July 2021  | 

Upgrading from a Z61 doublet which performed exceedingly well for wide field work. Haven't had a chance to take the GT71 for its first light just yet but I'm confident it will perform and exceed my expectations. Took a while to arrive due to covid circumstances but the FLO team were very patient on providing updates. As always top service. Thank you again!

Rating (max 5):  
Beautiful little telescope
27 July 2021  | 

I've only had a couple of clear nights so far so haven't had as much playtime as I would like, however from the use I have had I really can't fault it! The images are crisp, the stars are round, and for me the field of view is perfect! It is a very well made little scope and I can't wait to get more use out of it. As always the guys at FLO have been extremely helpful and the scope arrived in perfect condition!

Rating (max 5):  
Fine bit of Kit
28 May 2020  | 

Quite stunning workmanship everything is really precise the focus system is a joy. This is my first refractor I am more than happy with my purchase which I intend to use in conjunction with my DSLR. Took a few weeks to arrive as one of the ordered parts was not in stock and this virus problem. Never the less it arrived when they said it would and was well packed.


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