Vixen Optics SD103SII 103mm f/7.7 SD APO Refractor Telescope

Crystal-Clear Star Images with Pro-Level Precision

Dream of flawless star photos? The Vixen Optics SD103SII delivers razor-sharp, chromatic-aberration-free images without dealing with blurry distortions or halos. Elevate your astrophotography and stargazing with precision optics designed for professionals and enthusiasts alike.

Features

• 103mm SD Apochromatic Lens
  Precision optics featuring FPL53 Super ED glass significantly reduce chromatic aberration, delivering sharp, vibrant star images across all visible wavelengths.
• Upgraded Ring Spacers for Enhanced Star Images
  The SD103SII replaces traditional foil spacers with innovative ring-shaped spacers, ensuring uniform diffraction light. This eliminates radial breaks around stars, resulting in beautifully symmetrical and distortion-free star images—perfect for astrophotography.
• Astrophotography-Ready Design
  Compatible with optional SD Reducer HD and SD Flattener HD kits to create a 44mm image circle, ideal for full-frame DSLR and CMOS cameras.
• Dual Observation Modes
  Effortlessly switch between visual observation and photography with the included flip mirror diagonal. Attach a camera to one side and an eyepiece to the other for quick transitions without disrupting your setup. Use two eyepieces simultaneously for seamless magnification adjustments during observations.
• Focal Length Flexibility
  With the optional SD Reducer HD Kit, enjoy two effective focal lengths—811mm and 624mm in 35mm format. This versatility makes it ideal for capturing both wide-field nebulae and detailed planetary views.
• Precision Focusing
  Rack-and-pinion focuser with an optional dual-speed attachment provides 11:1 fine adjustments, ensuring perfect focus for high-magnification views or long-exposure shots.
• Enhanced Light Transmission
  The SD Reducer HD Kit and SD Flattener HD Kit feature advanced anti-reflection coatings, achieving 99.9% light transmission per surface. This ensures bright, high-contrast images with minimal light loss.
• 7x50mm Illuminated Finder Scope
  Locate celestial targets with a bright, clear field of view, featuring adjustable red-illuminated crosshairs for precision alignment. The customizable illumination levels ensure accurate sighting, even in the darkest skies.
• Chromatic Aberration Suppression
  The advanced SD glass lens minimizes chromatic aberration across all visible wavelengths, including g-ray (purple). This ensures vibrant star images with exceptional color fidelity, even at high magnifications.

The SD103SII is for You If…

• You want stunning, distortion-free star images with no chromatic aberration.
• You need a lightweight, portable telescope for dark-sky trips or stargazing events.
• You’re ready to capture nebulae, star clusters, and planets with professional-grade clarity.
• You value expandability, with optional accessories like reducers, flatteners, and dual-speed focusers.
• You love precision optics and want a telescope that grows with your astrophotography skills.
  

Unmatched Clarity and Precision

Discover stunning clarity with the Vixen Optics SD103SII. Its advanced SD glass lens, made from FPL53 Super ED material, eliminates chromatic aberration to deliver crisp, vibrant star images. Whether observing planets or photographing nebulae, this telescope offers results that rival professional standards.

In the SD glass lens, g-ray, C-ray, F-ray, d-ray, and e-ray wavelengths all come near the 0 value, indicating that chromatic aberration is held at an extremely low level across all visible colors. This superior optical performance particularly reduces aberration in the g-ray (purple), a short wavelength, resulting in crisp, high-fidelity star images with exceptional detail.

Enhanced Star Images with Ring-Shaped Spacers

The SD103SII improves on its predecessor, the SD103S, by upgrading the spacers used around the lens. In the former SD103S optical tube, small fragments of tin foil were set at three evenly spaced points around the lens as spacers. These fragments appeared inside the effective aperture and caused diffraction patterns, creating three radial breaks around star images.

The SD103SII replaces these fragments with an innovative ring-shaped spacer, ensuring uniform diffraction light. This upgrade eliminates the radial breaks and produces beautifully uniform star fields, elevating your astrophotography to professional-grade quality.

Versatility Across Observations and Imaging

With a reasonable focal length of 795mm and an objective effective aperture of 103mm, the SD103SII is ideal for a wide range of purposes. Use it for planetary observations, capturing nebulae, or photographing star clusters with outstanding clarity.

The supplied flip mirror diagonal simplifies switching between observation and photography. A quick-turn knob allows you to change the optical path to straight-through or vertical orientation. Attach a camera on one side and an eyepiece on the other, enabling rapid transitions between imaging and visual observing. Additionally, the system supports two eyepieces with different magnifications, allowing you to switch perspectives effortlessly.

Faint Object Observation Made Easy

With a resolving power of 1.13 arc seconds and a limiting magnitude of 11.8, the SD103SII is perfect for capturing faint celestial objects like distant galaxies, nebulae, and star clusters. Its 217x light-gathering capability ensures excellent visibility of faint objects, even under challenging conditions.

Specs at a Glance

What’s Included in the SD103SII Package?

With the SD103SII, you’re getting a complete setup ready to enhance your stargazing and astrophotography experience:

• Mounting Tube Rings: Secure and stabilize your telescope with precision-engineered rings for vibration-free observations and imaging.
• Diagonal Flip-Mirror: Quickly switch between observation and imaging with this user-friendly accessory.
• Dovetail Mounting Plate: Attach your telescope to various mounts with ease for seamless compatibility.
• Carry Handle: Transport your telescope effortlessly with a durable metal handle.
• Dust Covers: Protect your optics from dust and debris when not in use.
• 7x50 Finderscope: Pinpoint celestial targets with precision using the illuminated finderscope, featuring adjustable brightness and crosshairs for easy alignment.

Recommended Accessories:

Expand Your Field of View

• SD Reducer HD Kit: Reduces focal length by 0.79x for capturing expansive nebulae and star clusters with stunning clarity. With 99.9% light transmission per surface, it ensures bright, high-contrast images.
• SD Flattener HD Kit: Delivers a perfectly flat imaging field for full-frame DSLR and CMOS cameras. Anti-reflection coatings guarantee minimal light loss.

Optimize for Prime Focus Photography

• Wide Photo Adapter 60DX: Designed for Canon EOS and Nikon cameras, this adapter ensures precise alignment and minimal vignetting for astrophotography.

Achieve Pinpoint Precision

• Dual Speed Focuser: Offers 11:1 fine adjustments for high-magnification views and long-exposure shots.

Each accessory complements the SD103SII’s advanced features, helping you achieve professional-quality results with ease.

7x50mm Finder II with Illuminated Reticle

The included 7x50mm Finder II is a high-performance finder scope/guide scope designed to enhance your celestial observations and astrophotography. With a 7x magnification and a 50mm aperture, it offers a clear, wide field of view to help you quickly locate celestial targets.

• Illuminated Crosshairs for Precision Alignment
  The built-in dark field illumination lights up the crosshairs in red, making it easy to align objects in low-light conditions. The brightness is adjustable step by step, allowing you to customize the illumination to your preference.
• Detachable Eyepiece Unit
  The eyepiece unit features a 31.7mm sleeve and is detachable, adding versatility to the finder scope. By replacing the eyepiece unit with a commercially available CMOS camera (with a 31.7mm sleeve), the finder scope can be used as a guide scope for astrophotography.
• Compatibility Notes
  • Although you can insert 31.7mm eyepieces sold separately into the finder scope, they will not reach focus and are not functional for observation.
  • For compatibility with CMOS cameras, ensure that the distance from the 31.7mm visual back (rear end of the scope body) to the surface of the imaging sensor is approximately 15mm or less.

The 7x50mm Finder II is an essential tool for astronomers seeking precision in both observation and imaging, offering flexibility, reliability, and excellent usability under various conditions.