The SVBONY SV135 7–21mm Zoom Eyepiece (1.25") is a practical and affordable zoom eyepiece designed for astronomers who want flexible magnification without constantly changing eyepieces. Covering a useful 7mm to 21mm focal length range, it is well suited to lunar, planetary, and brighter deep-sky observation.
Key Features
- 7–21mm zoom eyepiece – adjust magnification smoothly without swapping eyepieces
- 5-element / 3-group optical design using high-index glass for sharp, high-contrast views
- 52°–36° apparent field of view across the zoom range
- 13–14mm eye relief with rubber eyecup for comfortable viewing
- Standard 1.25" barrel compatible with most telescopes and filters
- Safety undercut groove helps prevent accidental drops during use
Flexible Zoom for Lunar & Planetary Observation
The SV135 allows you to fine-tune magnification to match seeing conditions and targets. Lower magnification is ideal for locating objects and viewing the full lunar disc, while higher magnification is useful for examining details on the Moon, Jupiter, and Saturn. This flexibility makes the SV135 especially convenient for beginners and outreach sessions.
SV135 eyepiece is a helpful tool for observing and basic imaging of the Moon and planets, providing a more comfortable viewing experience on bright targets such as Jupiter and Saturn.
Optical Design & Image Quality
The 5-element, 3-group lens structure is designed to deliver good sharpness and contrast across the zoom range. Fully multi-coated optics help improve light transmission and reduce reflections, resulting in brighter images and more natural colour rendition.
Comfortable Viewing & Secure Fit
With a 13–14mm eye relief and a soft rubber eyecup, the SV135 remains comfortable during longer observing sessions, whether you observe with or without glasses. The standard 1.25" barrel includes a safety undercut to help ensure a secure fit in the focuser.
Simple Setup & Broad Compatibility
The SV135 is compatible with all telescopes that accept 1.25" eyepieces, including refractors, Maksutovs, Schmidt-Cassegrains, and Dobsonians. It also supports standard 1.25" filters, making it easy to expand your observing options.
Designed for Everyday Observing
The SV135 is a solid choice for users who want a lightweight, easy-to-use zoom eyepiece for regular observing. It offers a practical balance between convenience, optical performance, and affordability.
