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William Optics

Items 1 - 25 of 177
William Optics 40 mm Super Wide Angle Eyepiece - 2"

William Optics 40 mm Super Wide Angle 2" Eyepiece - E-SWA40

SKU: WYO-E-SWA40
  • Focal Length: 40 mm
  • Apparent Field of View: 72 degrees
  • Barrel Size: 2"
  • Eye Relief: 28 mm
$118.00
William Optics Soft Carry Case with No Foam for GTF81 and GT81 Refractors

William Optics Soft Carry Case for GTF81 and GT81 - No Foam - BG1-P002

SKU: WYO-BG1-P002
  • Case/Cover Dimensions (LxWxH): 20.55" x 7" x 13.25" - External
  • Known to Fit: William Optics GTF81 and GT81 Telescopes
$58.00
William Optics 1.25" Dielectric Diagonal with Carbon Fiber Side Plates

William Optics 1.25" Dielectric Diagonal W/ Carbon Fiber Plates - D-125D-C-DB

SKU: WYO-D-125D-C-DB
  • Diagonal Type: Mirror Diagonal
  • Diagonal Size - Eyepiece Side: 1.25" Barrel
  • Diagonal Size - Telescope Side: 1.25" Barrel
  • Optics Type and/or Coatings: Dielectric Coatings
$95.00
William Optics Binoviewer Package with Eyepieces & Barlow

William Optics Binoviewer W/Eyepieces & Barlow Nosepiece - E-BINO-P

SKU: WYO-E-BINO-P
  • For finetuning this William Optics Binoviewer has eyepiece focus adjustment.

  • This WO binoviewer has fully-multi coated optical elements.

  • Included with this Binoviewer are two William Optics 20 mm, 1.25" eyepieces.

  • The use of non-marring compression rings protect the inserted eyepieces.
$268.00
William Optics Soft Carry Case for 71 mm Telescopes - No Foam

William Optics Soft Carry Case for Z71 - No Foam - BG1-P004

SKU: WYO-BG1-P004
  • Case/Cover Dimensions (LxWxH): 15.75" x 6.5" x 12.5" - External
  • Known to Fit: William Optics Z71 Telescope
$59.00
William Optics 9 mm SWAN 1.25" Eyepiece

William Optics 9 mm Super Wide Angle 1.25" Eyepiece - E-SWA09

SKU: WYO-E-SWA09
  • Focal Length: 9 mm
  • Apparent Field of View: 72 degrees
  • Barrel Size: 1.25"
  • Eye Relief: 12 mm
$79.00
William Optics 45º Erect Prism - 1.25"

William Optics 1.25" 45° Erect Prism - D-EP125

SKU: WYO-D-EP125
  • Diagonal Type: Correct/Erect Image
  • Diagonal Size - Eyepiece Side: 1.25" Barrel
  • Diagonal Size - Telescope Side: 1.25" Barrel
$80.00
William Optics 20 mm SWAN Eyepiece - 1.25"

William Optics 20 mm Super Wide Angle 1.25" Eyepiece - E-SWA20

SKU: WYO-E-SWA20
  • Focal Length: 20 mm
  • Apparent Field of View: 72 degrees
  • Barrel Size: 1.25"
  • Eye Relief: 17 mm
$79.00
William Optics Soft Carry Case for FLT98, FLT110, GT102, & GTF102 - No Foam

William Optics Soft Carry Case for FLT98, FLT110, GT102, GTF102 - No Foam - BG1-P001

SKU: WYO-BG1-P001
  • Case/Cover Dimensions (LxWxH): 30.315" x 13.7795" x 9.44882" (770mm x 350mm x 240mm) - External
  • Known to Fit: William Optics FLT98, FLT110, GT102, GTF102 Telescopes
$168.00

William Optics Zenithstar 81 APO Refractor Package with 0.8x Reducer & Flattener - Red - A-Z81RD-AP

SKU: WYO-A-Z81RD-AP
  • Optical Design: Refractor
  • Telescope Aperture: 81mm (3.19")
  • Focal Ratio: f/6.9
  • Telescope Mount Type: No Mount - OTA Only
  • Type of Electronics: OTA Only - No Electronics
Free shipping Free shipping
$918.00

William Optics Star71 Four Element f/4.9 Imaging Refractor w/2.5" Focuser - A-WO71-II - Used - SOLD

SKU: UEQ-2016-21
  • Optical Design: Refractor
  • Telescope Aperture: 71mm (2.8")
  • Focal Ratio: f/4.9
  • Telescope Mount Type: No Mount - OTA Only
  • Type of Electronics: OTA Only - No Electronics
$1,198.00 $980.00

William Optics Dura Bright 2" Carbon Dielectric Diagonal - D-DIG2D-C-DB

SKU: WYO-D-DIG2D-C-DB
  • Diagonal Type: Mirror Diagonal
  • Diagonal Size - Eyepiece Side: 2" Barrel
  • Diagonal Size - Telescope Side: 2" Barrel
  • Includes Eyepiece Adapter: Yes, 2" to 1.25"
  • Optics Type and/or Coatings: Dielectric Coatings
$139.00

William Optics 0.8x Reducer/Flattener - P-FLAT7A

SKU: WYO-P-FLAT7A
  • This William Optics 0.8x reducer/flattener is adjustable for optimum back focus.
  • Adjustment depends on the William Optics refractor with which the flattener is used.
  • This flattener is meant to work with the FLT132, FLT156, GT102, GT153, and the Z126.
  • The FLAT7A is compatible with several types of CCD and CMOS cameras.
  • The flattener is produced with Ohara optical glass.
$598.00

William Optics Cat Series Saddle Handle Bar - Red - M-HCRC-RD

SKU: WYO-M-HCRC-RD
  • Type of Mounting Hardware: Mount Adapters, Stalks & Accessories
  • Color: Red
  • Telescope Compatibility: RedCat, WhiteCat, SpaceCat
  • Ring/GuideScope Compatibility: WO UniGuide, Vixen Style Guide Scopes
$45.00

William Optics Cat Series Saddle Handle Bar - Black - M-HCRC-BL

SKU: WYO-M-HCRC-BL
  • Type of Mounting Hardware: Mount Adapters, Stalks & Accessories
  • Color: Black
  • Telescope Compatibility: RedCat, WhiteCat, SpaceCat
  • Ring/GuideScope Compatibility: WO UniGuide, Vixen Style Guide Scopes
$45.00

William Optics Cat Series Mounting Ring - M-MR50RC-BL

SKU: WYO-M-MR50RC-BL
  • Type of Mounting Hardware: Rings Only
  • Ring Size: 50 mm (1.9")
  • Solid or Split (Cradle) Ring: Solid
$39.00

William Optics 800 mm Mortar Tri-Pier - Red - YG-MT-800-BR

SKU: WYO-YG-MT-800-BR
  • This William Optics tri-pier is made out of 6061T Aluminum and Stainless Steel.
  • The maximum height of the tri-pier is either 800 mm.
  • William Optics Tri-Pier is compatible with iOptron, Sky-Watcher, Crux, Takahashi, and Vixen mounts.
  • Choosing this WO tripod means you will have the stability of a pier with the flexibility of a tripod.
Free shipping Free shipping
$628.00

William Optics Image Plane Tilt Adjuster for Cat51 Upgrade - M-FD-RC51

SKU: WYO-M-FD-RC51
  • Made for Cat Series Refractors
  • Comes with a M48 Filter Thread
  • Used as an upgrade for first generation Cat Series Scopes
  • Includes push screws and pull screws
$45.00
$45.00

William Optics 1.25" RotoLock Adapter - Gold - F-ROTO-A2-125GDII

SKU: WYO-F-ROTO-A2-125GDII
  • This Rotolock adapter locks into the 2” opening of a WO Rotolock diagonal or focuser.
  • This is a steppingstone to attaching 1.25” barreled accessories.
  • Rotating the adapter ring will lock and unlock the inserted accessory into place.
  • Using this adapter will ensure that your accessory is centered.
$45.00

William Optics 1000 mm Mortar Tri-Pier - Red - YG-MT-1000-BR

SKU: WYO-YG-MT-1000-BR
  • This William Optics tri-pier is made out of 6061T Aluminum and Stainless Steel.
  • The maximum height of the tri-pier is 1000 mm.
  • William Optics Tri-Pier is compatible with iOptron, Sky-Watcher, Crux, Takahashi, and Vixen mounts.
  • Choosing this WO tripod means you will have the stability of a pier with the flexibility of a tripod.
$628.00

William Optics 1000 mm Mortar Tri-Pier w/ iOptron Adapter - Red - YG-MT-1000-BR-IOPTRON

SKU: WYO-YG-MT-1000-BR-IOPTRON
  • This William Optics tri-pier is made out of 6061T Aluminum and Stainless Steel.
  • The maximum height of the tri-pier is 1000 mm.
  • William Optics Tri-Pier is compatible with iOptron, Sky-Watcher, Crux, Takahashi, and Vixen mounts.
  • Choosing this WO tripod means you will have the stability of a pier with the flexibility of a tripod.
$628.00

William Optics 800 mm Mortar Tri-Pier - Red - YG-MT-800-BR-IOPTRON

SKU: WYO-YG-MT-800-BR-IOPTRON
  • This William Optics tri-pier is made out of 6061T Aluminum and Stainless Steel.
  • The maximum height of the tri-pier is either 800 mm.
  • William Optics Tri-Pier is compatible with iOptron, Sky-Watcher, Crux, Takahashi, and Vixen mounts.
  • Choosing this WO tripod means you will have the stability of a pier with the flexibility of a tripod.
Free shipping Free shipping
$628.00

William Optics 1000 mm Mortar Tri-Pier w/ iOptron Adapter - Gold - YG-MT-1000-GB-IOPTRON

SKU: WYO-YG-MT-1000-GB-IOPTRON
  • This William Optics tri-pier is made out of 6061T Aluminum and Stainless Steel.
  • The maximum height of the tri-pier is 1000 mm.
  • William Optics Tri-Pier is compatible with iOptron, Sky-Watcher, Crux, Takahashi, and Vixen mounts.
  • Choosing this WO tripod means you will have the stability of a pier with the flexibility of a tripod.
$628.00

William Optics 1000 mm Mortar Tri-Pier - Gold - YG-MT-1000-GB

SKU: WYO-YG-MT-1000-GB
  • This William Optics tri-pier is made out of 6061T Aluminum and Stainless Steel.
  • The maximum height of the tri-pier is 1000 mm.
  • William Optics Tri-Pier is compatible with iOptron, Sky-Watcher, Crux, Takahashi, and Vixen mounts.
  • Choosing this WO tripod means you will have the stability of a pier with the flexibility of a tripod.
$628.00

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!

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