The SVBONY SV230 8–20mm Click-Stop Zoom Eyepiece is a high-performance wide-angle zoom eyepiece designed for astronomers who want flexibility, optical quality, and viewing comfort without constantly changing eyepieces. Covering a useful focal length range from 8mm to 20mm, it delivers a continuously adjustable magnification with an expansive 57°–72° apparent field of view.

• 8–20mm continuous zoom eyepiece for planetary and deep-sky observing
• Click-stop zoom mechanism for precise, repeatable magnification changes
• Wide 57°–72° apparent field of view across the zoom range
• Parfocal design minimises refocusing when changing magnification
• Aspherical optical elements for improved edge sharpness
• Fully multi-coated optics for enhanced contrast and light transmission
• Blackened lens edges to reduce internal reflections and stray light
• Long 17–19mm eye relief, suitable for eyeglass wearers
• Dual 1.25" and 2" barrels for broad telescope compatibility

Click-Stop Zoom & Parfocal Optical Design

The precision click-stop zoom mechanism allows smooth and accurate transitions between focal lengths, making it easy to fine-tune magnification while observing planets, the Moon, or deep-sky objects. Thanks to its parfocal construction, focus remains largely consistent across the entire zoom range, saving time and improving observing flow during live sessions.

Wide-Angle Viewing from 57° to 72°

Unlike traditional narrow-field zoom eyepieces, the SV230 delivers a genuinely immersive experience. The apparent field of view expands from 57° at 20mm to a wide 72° at 8mm, providing a more natural and engaging view when tracking objects manually or observing extended deep-sky targets. Each focal position is optically optimised to maintain a consistent wide-angle feel.

Aspherical Optics & High-Contrast Performance

The optical system uses aspherical lens elements to improve edge performance and suppress distortion, a common weakness in wide-angle zoom eyepieces. Combined with fully multi-coated glass and blackened lens edges, the SV230 delivers higher contrast, improved light transmission, and cleaner backgrounds — particularly beneficial when observing faint deep-sky objects under light-polluted skies.

Dual 1.25" & 2" Compatibility

Supplied with both 1.25" and 2" nosepieces, the SV230 integrates seamlessly with a wide range of telescopes, including Dobsonians, Schmidt-Cassegrains, Maksutovs, and refractors. Filter threads are provided on both barrel sizes, allowing easy use of standard astronomical filters.

Comfortable Viewing & Astigmatism Support

With a generous 17–19mm eye relief and an adjustable rubber eyecup, the SV230 provides a relaxed viewing experience, even during long observing sessions. The eyecup can be removed to reveal an M43 thread, allowing connection to compatible astigmatism correctors via an optional adapter (not included).

Who Is This Eyepiece For?

The SVBONY SV230 is ideal for observers who want a single premium zoom eyepiece to cover multiple magnifications, particularly for lunar, planetary, and brighter deep-sky observing. It is especially well suited to Dobsonian users, outreach sessions, and astronomers who value convenience without sacrificing optical quality.