William Optics ZenithStar 71mm f/5.9 Doublet ED Refractor - 20th Anniversary Edition
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Special Offer: Save $50 when you purchase this item with the William Optics 1.25" 99% Dielectric Dura Bright Carbon Fiber Star Mirror Diagonal. Just add both items to your cart and the discount will be automatically applied. Offer valid ONLY if you purchase both items (William Optics ZenithStar A-Z71A-VP20A & William Optics 1.25" Diagonal D-125D-C-DB) in the same transaction.
ZS71 20th Anniversary Edition in Red Color
A small-aperture, extremely-portable ED scope at a GREAT price? The latest ZS 71 ED Doublet is here to fit all your needs!
Excellent mechanics, fit and finish, with the latest WO 2" Rack & Pinion 2-speed fine focuser. Improved focuser is so good that it replicates the smoothness and lack of backlash normally associated with a Crayford focuser, but with the huge advantage of much increased mechanical strength.
Lens Design
- ED glass (Japanese imported Ohara glass) doublet air-spaced, in CNC machined ultra-high precision lens cell.
- Each lens is Fully Multi-Coated with a special super-high transmission coating (STM Coating) on all surfaces.
Low CA
- Fully baffled to block all extraneous off-axis light rays and prevent glancing reflections, increasing overall contrast.
- 71 mm clear aperture and F/5.9 focal ratio.
Nothing Left to Chance
- Perfect for Vixen-style mount dovetail bases. You can slide it directly into the mount without a dovetail plate if you like.
- Pure William Optics quality fit and finish: powder-painted white CNC-machined aluminum tube
- Drawtube travel length 80 mm with graduated scale.
- Retractable dewshield, smallest size ever and enhanced portability!
- Can mount a WO 2'' star diagonal and other 2" accessories.
Astrophotography ED Scope
- Fast focal ratio for bright, high-quality astro-imaging.
- Perfect for piggybacking as a guide scope.
Wonderful WO Microfocuser
- New rotatable Rack & Pinion focuser, smooth and precise, ideal during astrophotography; can be fully locked and will not flex or slip even with a very heavy camera combination.
- Adjustable focuser tension.
- Super-smooth and reliable 1:10 micro focuser for fine focusing during imaging and visual observations alike.
- Aluminum fine knob protection cover is included.
Attention to Packaging
- The basic package includes the OTA only.
- Carry-on size: you do not have to leave this treasure home.
- Two-year, no fuss warranty and constant customer service!
Specification for William Optics Lenses
The ZS71 20th Anniversary Edition includes a FREE soft carry bag.
All William Optics refractor objectives are double tested and inspected by WO at their factory. These telescopes are free of coma and astigmatism. Since all individual lens surfaces are machine coated, sometimes you may notice minor visual imperfections which will not compromise the optical performance of the telescope. The dimensions of scratches and points shall not exceed the following values:
- Scratches - Maximum Width: 0.025 mm
- Scratches - Maximum Length: 1/4 of total lens diameter
- Scratches - Maximum Quantity: Three
- Dots or Spot Points - Maximum Diameter: 0.4 mm
- Dots or Spot Points - Maximum Quantity: Three
- Accumulation of Defects - Limited Area: 0.8mm^2
- Accumulation of Defects - Total Area: 5.8mm^2
ZS71 20th Anniversary Edition in Red Color
A small-aperture, extremely-portable ED scope at a GREAT price? The latest ZS 71 ED Doublet is here to fit all your needs!
Excellent mechanics, fit and finish, with the latest WO 2" Rack & Pinion 2-speed fine focuser. Improved focuser is so good that it replicates the smoothness and lack of backlash normally associated with a Crayford focuser, but with the huge advantage of much increased mechanical strength.
Lens Design
- ED glass (Japanese imported Ohara glass) doublet air-spaced, in CNC machined ultra-high precision lens cell.
- Each lens is Fully Multi-Coated with a special super-high transmission coating (STM Coating) on all surfaces.
Low CA
- Fully baffled to block all extraneous off-axis light rays and prevent glancing reflections, increasing overall contrast.
- 71 mm clear aperture and F/5.9 focal ratio.
Nothing Left to Chance
- Perfect for Vixen-style mount dovetail bases. You can slide it directly into the mount without a dovetail plate if you like.
- Pure William Optics quality fit and finish: powder-painted white CNC-machined aluminum tube
- Drawtube travel length 80 mm with graduated scale.
- Retractable dewshield, smallest size ever and enhanced portability!
- Can mount a WO 2'' star diagonal and other 2" accessories.
Astrophotography ED Scope
- Fast focal ratio for bright, high-quality astro-imaging.
- Perfect for piggybacking as a guide scope.
Wonderful WO Microfocuser
- New rotatable Rack & Pinion focuser, smooth and precise, ideal during astrophotography; can be fully locked and will not flex or slip even with a very heavy camera combination.
- Adjustable focuser tension.
- Super-smooth and reliable 1:10 micro focuser for fine focusing during imaging and visual observations alike.
- Aluminum fine knob protection cover is included.
Attention to Packaging
- The basic package includes the OTA only.
- Carry-on size: you do not have to leave this treasure home.
- Two-year, no fuss warranty and constant customer service!
Specification for William Optics Lenses
The ZS71 20th Anniversary Edition includes a FREE soft carry bag.
All William Optics refractor objectives are double tested and inspected by WO at their factory. These telescopes are free of coma and astigmatism. Since all individual lens surfaces are machine coated, sometimes you may notice minor visual imperfections which will not compromise the optical performance of the telescope. The dimensions of scratches and points shall not exceed the following values:
- Scratches - Maximum Width: 0.025 mm
- Scratches - Maximum Length: 1/4 of total lens diameter
- Scratches - Maximum Quantity: Three
- Dots or Spot Points - Maximum Diameter: 0.4 mm
- Dots or Spot Points - Maximum Quantity: Three
- Accumulation of Defects - Limited Area: 0.8mm^2
- Accumulation of Defects - Total Area: 5.8mm^2
| Manufacturer | William Optics |
|---|
| Aperture | 71mm |
| Focal Ratio | F/5.9 |
| Focal Length | 418 mm |
| Objective Type | ED Doublet, Air Spaced, Fully Multi-Coated, SMT coating. |
| Resolving Power | 1.58" |
| Limiting Magnitude | 11 |
| Lens Shade | Retractable |
| Focuser | 50.8mm (2") Rack & Pinion Focuser with 1:10 Dual Speed microfocuser 80 mm (3.2") Focuser Travel Length 360° Rotatable Design |
| 1.25" Adapter | Brass Compression Rings |
| L-type Mount | Integrated L Bracket |
| Field Stops | Baffles |
| Tube Diameter | X mm (X") |
| Tube Length | X mm Fully Retracted X mm Fully Extended |
| Tube Weight | X lbs. (X kg) |
Special Offer: Save $50 when you purchase this item with the William Optics 1.25" 99% Dielectric Dura Bright Carbon Fiber Star Mirror Diagonal. Just add both items to your cart and the discount will be automatically applied. Offer valid ONLY if you purchase both items (William Optics ZenithStar A-Z71A-VP20A & William Optics 1.25" Diagonal D-125D-C-DB) in the same transaction.
ZS71 20th Anniversary Edition in Red Color
A small-aperture, extremely-portable ED scope at a GREAT price? The latest ZS 71 ED Doublet is here to fit all your needs!
Excellent mechanics, fit and finish, with the latest WO 2" Rack & Pinion 2-speed fine focuser. Improved focuser is so good that it replicates the smoothness and lack of backlash normally associated with a Crayford focuser, but with the huge advantage of much increased mechanical strength.
Lens Design
- ED glass (Japanese imported Ohara glass) doublet air-spaced, in CNC machined ultra-high precision lens cell.
- Each lens is Fully Multi-Coated with a special super-high transmission coating (STM Coating) on all surfaces.
Low CA
- Fully baffled to block all extraneous off-axis light rays and prevent glancing reflections, increasing overall contrast.
- 71 mm clear aperture and F/5.9 focal ratio.
Nothing Left to Chance
- Perfect for Vixen-style mount dovetail bases. You can slide it directly into the mount without a dovetail plate if you like.
- Pure William Optics quality fit and finish: powder-painted white CNC-machined aluminum tube
- Drawtube travel length 80 mm with graduated scale.
- Retractable dewshield, smallest size ever and enhanced portability!
- Can mount a WO 2'' star diagonal and other 2" accessories.
Astrophotography ED Scope
- Fast focal ratio for bright, high-quality astro-imaging.
- Perfect for piggybacking as a guide scope.
Wonderful WO Microfocuser
- New rotatable Rack & Pinion focuser, smooth and precise, ideal during astrophotography; can be fully locked and will not flex or slip even with a very heavy camera combination.
- Adjustable focuser tension.
- Super-smooth and reliable 1:10 micro focuser for fine focusing during imaging and visual observations alike.
- Aluminum fine knob protection cover is included.
Attention to Packaging
- The basic package includes the OTA only.
- Carry-on size: you do not have to leave this treasure home.
- Two-year, no fuss warranty and constant customer service!
Specification for William Optics Lenses
The ZS71 20th Anniversary Edition includes a FREE soft carry bag.
All William Optics refractor objectives are double tested and inspected by WO at their factory. These telescopes are free of coma and astigmatism. Since all individual lens surfaces are machine coated, sometimes you may notice minor visual imperfections which will not compromise the optical performance of the telescope. The dimensions of scratches and points shall not exceed the following values:
- Scratches - Maximum Width: 0.025 mm
- Scratches - Maximum Length: 1/4 of total lens diameter
- Scratches - Maximum Quantity: Three
- Dots or Spot Points - Maximum Diameter: 0.4 mm
- Dots or Spot Points - Maximum Quantity: Three
- Accumulation of Defects - Limited Area: 0.8mm^2
- Accumulation of Defects - Total Area: 5.8mm^2
| Manufacturer | William Optics |
|---|
| Aperture | 71mm |
| Focal Ratio | F/5.9 |
| Focal Length | 418 mm |
| Objective Type | ED Doublet, Air Spaced, Fully Multi-Coated, SMT coating. |
| Resolving Power | 1.58" |
| Limiting Magnitude | 11 |
| Lens Shade | Retractable |
| Focuser | 50.8mm (2") Rack & Pinion Focuser with 1:10 Dual Speed microfocuser 80 mm (3.2") Focuser Travel Length 360° Rotatable Design |
| 1.25" Adapter | Brass Compression Rings |
| L-type Mount | Integrated L Bracket |
| Field Stops | Baffles |
| Tube Diameter | X mm (X") |
| Tube Length | X mm Fully Retracted X mm Fully Extended |
| Tube Weight | X lbs. (X kg) |