Vixen Optics SD81S II f/7.7 Apo Doublet Refractor Telescope - OTA Only
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- 81mm SD apochromatic doublet minimizes chromatic aberration for sharp views
- 625mm Focal Length (f/7.7) is ideal for lunar, planetary, and deep-sky observing and imaging
- Ring-shaped lens spacer eliminates diffraction spikes for cleaner, rounder stars
- Lightweight optical tube with included carry handle, dovetail bar, and 1.25" flip mirror diagonal
Vixen SD81SII Optical Tube Assembly
The Vixen SD81SII is a versatile 81mm f/7.7 apochromatic refractor telescope designed to deliver sharp, high-contrast views and stunning astrophotography results! Featuring premium FPL53 Super ED glass and multi-coated optics, this telescope significantly reduces chromatic aberration for crisp, detailed images of the Moon, planets, nebulae, and star clusters.
With its 625mm focal length, the SD81SII offers an excellent balance between visual observing and deep-sky imaging. An improved ring-shaped lens spacer provides more uniform diffraction patterns for cleaner, more natural-looking stars, while its compact design makes setup and transportation easy. Please note: Eyepieces imaged above are not included and for demonstration purposes only.
Sharper, More Refined Stars with Improved SD Optics
The Vixen SD81SII features an upgraded ring-shaped lens spacer that replaces the three small foil spacers used in the previous SD81S model. These older spacers slightly obstructed incoming light, creating uneven diffraction patterns around stars. The new ring design eliminates these obstructions, producing more uniform diffraction patterns and cleaner, more natural-looking stars in astrophotography.
Combined with premium FPL53 Super ED glass, the SD81SII significantly reduces chromatic aberration by bringing different wavelengths of light closer to a common focus. The result is sharper, high-contrast images with minimal color fringing, ideal for both visual observing and astrophotography.
Exceptional Color Correction for Sharp, High-Contrast Images
The Vixen SD81SII features premium SD glass that brings multiple wavelengths of visible light, from red to violet, into nearly the same focal plane. This advanced optical design significantly reduces chromatic aberration, including violet light fringing that can affect image contrast and clarity.
With excellent color correction and a versatile f/7.7 focal ratio, the SD81SII delivers sharp, high-contrast views with minimal color distortion, making it an excellent choice for both visual astronomy and astrophotography.
Compact, Lightweight Design for Easy Setup and Imaging
The Vixen SD81SII features a compact, lightweight optical tube that's easy to transport, set up, and balance with fewer counterweights. An included metal carrying handle and Vixen dovetail mounting plate make attaching and removing the telescope quick and convenient.
The included flip mirror diagonal adds versatility by allowing you to switch between two eyepieces with different magnifications or use a camera and eyepiece simultaneously for easier target framing and astrophotography.
Specifications
- Aperture: 81 mm SD (Super ED) apochromatic doublet
- Focal Length: 625 mm
- Focal Ratio: f/7.7
- Resolving Power: 1.43 arcseconds
- Limiting Magnitude: 11.3
- Light-Gathering Power: 134x
- Focuser: Rack-and-pinion with lock knob
- Finderscope: XY Red Dot Finder II (1x aiming device)
- Adapter Threads: M60 (Adapters Required)
- Photography Compatibility: Prime focus, eyepiece projection, and afocal imaging
- Optical Tube Dimensions: 90 mm diameter x 585 mm length
- Weight: 3.6 kg (7.94 lb) with accessories; 2.3 kg (5.07 lb) optical tube only
Using an SD reducer HD kit or an SD Flattener SD kit, which are available optionally, the SD80SII provides an image circle of 44mm, adequate for taking photos with a DSLR camera. (Photo) M8, M20 nebulae taken with Vixen SD81SII with SD reducer HD kit (compound focus 496mm) and Pentax K-1 at ISO1600, 49 minutes exposure.
Other Information
- Country of Manufacture: Japan
Vixen SD81SII Optical Tube Assembly
The Vixen SD81SII is a versatile 81mm f/7.7 apochromatic refractor telescope designed to deliver sharp, high-contrast views and stunning astrophotography results! Featuring premium FPL53 Super ED glass and multi-coated optics, this telescope significantly reduces chromatic aberration for crisp, detailed images of the Moon, planets, nebulae, and star clusters.
With its 625mm focal length, the SD81SII offers an excellent balance between visual observing and deep-sky imaging. An improved ring-shaped lens spacer provides more uniform diffraction patterns for cleaner, more natural-looking stars, while its compact design makes setup and transportation easy. Please note: Eyepieces imaged above are not included and for demonstration purposes only.
Sharper, More Refined Stars with Improved SD Optics
The Vixen SD81SII features an upgraded ring-shaped lens spacer that replaces the three small foil spacers used in the previous SD81S model. These older spacers slightly obstructed incoming light, creating uneven diffraction patterns around stars. The new ring design eliminates these obstructions, producing more uniform diffraction patterns and cleaner, more natural-looking stars in astrophotography.
Combined with premium FPL53 Super ED glass, the SD81SII significantly reduces chromatic aberration by bringing different wavelengths of light closer to a common focus. The result is sharper, high-contrast images with minimal color fringing, ideal for both visual observing and astrophotography.
Exceptional Color Correction for Sharp, High-Contrast Images
The Vixen SD81SII features premium SD glass that brings multiple wavelengths of visible light, from red to violet, into nearly the same focal plane. This advanced optical design significantly reduces chromatic aberration, including violet light fringing that can affect image contrast and clarity.
With excellent color correction and a versatile f/7.7 focal ratio, the SD81SII delivers sharp, high-contrast views with minimal color distortion, making it an excellent choice for both visual astronomy and astrophotography.
Compact, Lightweight Design for Easy Setup and Imaging
The Vixen SD81SII features a compact, lightweight optical tube that's easy to transport, set up, and balance with fewer counterweights. An included metal carrying handle and Vixen dovetail mounting plate make attaching and removing the telescope quick and convenient.
The included flip mirror diagonal adds versatility by allowing you to switch between two eyepieces with different magnifications or use a camera and eyepiece simultaneously for easier target framing and astrophotography.
Specifications
- Aperture: 81 mm SD (Super ED) apochromatic doublet
- Focal Length: 625 mm
- Focal Ratio: f/7.7
- Resolving Power: 1.43 arcseconds
- Limiting Magnitude: 11.3
- Light-Gathering Power: 134x
- Focuser: Rack-and-pinion with lock knob
- Finderscope: XY Red Dot Finder II (1x aiming device)
- Adapter Threads: M60 (Adapters Required)
- Photography Compatibility: Prime focus, eyepiece projection, and afocal imaging
- Optical Tube Dimensions: 90 mm diameter x 585 mm length
- Weight: 3.6 kg (7.94 lb) with accessories; 2.3 kg (5.07 lb) optical tube only
Using an SD reducer HD kit or an SD Flattener SD kit, which are available optionally, the SD80SII provides an image circle of 44mm, adequate for taking photos with a DSLR camera. (Photo) M8, M20 nebulae taken with Vixen SD81SII with SD reducer HD kit (compound focus 496mm) and Pentax K-1 at ISO1600, 49 minutes exposure.
| Manufacturer | Vixen Optics |
|---|---|
| Telescope Focal Length | 601 - 700mm |
- 1x SD81SII OTA
- 1x 1.25" Flip Mirror Diagonal
- 1x XY Red Dot Finder II
- 1x Dovetail Slide Bar M
- 1x Tube Rings
- 1x Instruction Manual
- 81mm SD apochromatic doublet minimizes chromatic aberration for sharp views
- 625mm Focal Length (f/7.7) is ideal for lunar, planetary, and deep-sky observing and imaging
- Ring-shaped lens spacer eliminates diffraction spikes for cleaner, rounder stars
- Lightweight optical tube with included carry handle, dovetail bar, and 1.25" flip mirror diagonal
Vixen SD81SII Optical Tube Assembly
The Vixen SD81SII is a versatile 81mm f/7.7 apochromatic refractor telescope designed to deliver sharp, high-contrast views and stunning astrophotography results! Featuring premium FPL53 Super ED glass and multi-coated optics, this telescope significantly reduces chromatic aberration for crisp, detailed images of the Moon, planets, nebulae, and star clusters.
With its 625mm focal length, the SD81SII offers an excellent balance between visual observing and deep-sky imaging. An improved ring-shaped lens spacer provides more uniform diffraction patterns for cleaner, more natural-looking stars, while its compact design makes setup and transportation easy. Please note: Eyepieces imaged above are not included and for demonstration purposes only.
Sharper, More Refined Stars with Improved SD Optics
The Vixen SD81SII features an upgraded ring-shaped lens spacer that replaces the three small foil spacers used in the previous SD81S model. These older spacers slightly obstructed incoming light, creating uneven diffraction patterns around stars. The new ring design eliminates these obstructions, producing more uniform diffraction patterns and cleaner, more natural-looking stars in astrophotography.
Combined with premium FPL53 Super ED glass, the SD81SII significantly reduces chromatic aberration by bringing different wavelengths of light closer to a common focus. The result is sharper, high-contrast images with minimal color fringing, ideal for both visual observing and astrophotography.
Exceptional Color Correction for Sharp, High-Contrast Images
The Vixen SD81SII features premium SD glass that brings multiple wavelengths of visible light, from red to violet, into nearly the same focal plane. This advanced optical design significantly reduces chromatic aberration, including violet light fringing that can affect image contrast and clarity.
With excellent color correction and a versatile f/7.7 focal ratio, the SD81SII delivers sharp, high-contrast views with minimal color distortion, making it an excellent choice for both visual astronomy and astrophotography.
Compact, Lightweight Design for Easy Setup and Imaging
The Vixen SD81SII features a compact, lightweight optical tube that's easy to transport, set up, and balance with fewer counterweights. An included metal carrying handle and Vixen dovetail mounting plate make attaching and removing the telescope quick and convenient.
The included flip mirror diagonal adds versatility by allowing you to switch between two eyepieces with different magnifications or use a camera and eyepiece simultaneously for easier target framing and astrophotography.
Specifications
- Aperture: 81 mm SD (Super ED) apochromatic doublet
- Focal Length: 625 mm
- Focal Ratio: f/7.7
- Resolving Power: 1.43 arcseconds
- Limiting Magnitude: 11.3
- Light-Gathering Power: 134x
- Focuser: Rack-and-pinion with lock knob
- Finderscope: XY Red Dot Finder II (1x aiming device)
- Adapter Threads: M60 (Adapters Required)
- Photography Compatibility: Prime focus, eyepiece projection, and afocal imaging
- Optical Tube Dimensions: 90 mm diameter x 585 mm length
- Weight: 3.6 kg (7.94 lb) with accessories; 2.3 kg (5.07 lb) optical tube only
Using an SD reducer HD kit or an SD Flattener SD kit, which are available optionally, the SD80SII provides an image circle of 44mm, adequate for taking photos with a DSLR camera. (Photo) M8, M20 nebulae taken with Vixen SD81SII with SD reducer HD kit (compound focus 496mm) and Pentax K-1 at ISO1600, 49 minutes exposure.
Other Information
- Country of Manufacture: Japan
| Manufacturer | Vixen Optics |
|---|---|
| Telescope Focal Length | 601 - 700mm |
- 1x SD81SII OTA
- 1x 1.25" Flip Mirror Diagonal
- 1x XY Red Dot Finder II
- 1x Dovetail Slide Bar M
- 1x Tube Rings
- 1x Instruction Manual