- William Optics 68III Field Flattener made for use with f/6 to f/7/5 focal ratio refractor telescopes.
- Offers compatibility with FLT132 and 102GTS apochromatic refractors, as well as other refractors with M92 focuser thread.
- Provides coverage for DSLR cameras with full size 50 mm clear lens aperture.
- Accepts standard M48 threaded camera t-rings.
- Threaded and blackened internal surfaces eradicate reflections.
- Protective covers are included for both sides.
- ZenithStar 73 Field Flattener
- M63 threads attaches directly to the Z73 after focus adapter has been removed
- The Z73 Flattener is adjustable up to 15mm to achieve perfect back focus
- A locking ring holds your back focus adjustment firmly in place
- Camera side has M48 threads to accept a wide T-ring (sold separately)
- Gold metal caps for both ends protect the Field Flattener when not in use
- Flattener for William Optics ZenithStar 61 (Z61) refractors
- M63 threads on the telescope side attach directly to the Z61 focuser
- M48 threads on the camera side accept a "wide" T-ring (sold separately)
- Adjustable up to 12mm to achieve perfect back focus
- Back focus is 55 mm, image circle is 43 mm
William Optics provides quality refractors, mounts, and accessories such as eyepieces, diagonals, and mounting hardware for amateur astronomers around the world. The CEO of the company is David Yang, an avid amateur astronomer and bird-watcher who feels strongly about offering premium optics to everyone with an interest in astronomy or nature, and not just to those with plenty of cash to spare.
When William Yang was a child, he thumbed through the pages of Sky & Telescope magazine and gazed at the beautiful images of our universe laid before him. His family could not afford to buy him a telescope, but he could dream of a day when he would be able to photograph galaxies and nebulae like the astrophotographers he admired so much. In 1986, David saved up all summer to buy a telescope to watch Halley's Comet, but before that he tried his hand at building his own telescopes with whatever supplies he could find; he even "borrowed" his grandmother's eyeglasses to use as the lenses for his first refractor!
In 1996, David opened William Optics in Taiwan. Four years later, in 2000, William Optics USA began by offering their break-out 80mm Megrez refractor to consumers in the United States. The quality, as well as the price, was amazing, and before long, William Optics had positioned themselves as one of the world leaders in fast, highly portable quality refractors.
William Optics also makes some great telescope accessories. Their WO Diagonals are celebrated the world over for their machining and optical quality, and their Ultra Wide Angle (UWA) and Super Wide Angle (SWA) eyepieces, with their unusual jet-black insertion barrels, have come to be known for their quality, but at an affordable price. We think William Yang has achieved what he set out to do; providing "More Quality for Less Money"; and we look forward to what he plans to do next!