SVBONY SV245 8–16 mm Zoom Eyepiece (1.25″ / 2″, 63°)

Product Overview

The SVBONY SV245 is an 8–16 mm zoom eyepiece with a 63° apparent field of view, a dual 1.25″ and 2″ barrel and click stops at each focal-length setting. Its 8-element, 5-group optical design is fully multi-coated with blackened lens edges, eye relief is 17–18 mm, and the eyepiece is parfocal across the zoom range. It measures 129 x 60 mm and weighs 486 g.

Who It's For

This is a good match if you observe the Moon and planets and want to step between magnifications to match the seeing without swapping eyepieces, if you observe with glasses and need room at the eyecup, or if you use an SVBONY spotting scope that SVBONY lists as compatible.

Key Features & Design

• 8–16 mm, 2x zoom: a 63° apparent field that stays consistent as you zoom.
• 8 elements in 5 groups: fully multi-coated optics with blackened lens edges for contrast.
• Click-stop design: a detent at each focal length from 8 mm to 16 mm for repeatable settings without play.
• Parfocal: focus holds closely through the zoom range.
• 17–18 mm eye relief: with a folding rubber eye guard for observing with or without glasses.
• Dual barrel: stainless-steel 1.25″ barrel and aluminium-alloy 2″ barrel, with M28.5 x 0.6 and M48 x 0.75 filter threads.
• Astigmatism corrector support: mainstream correctors can be fitted.

Optical Design

The eight elements are arranged in five groups, with multi-coating on every air-to-glass surface and blackened edges to suppress stray light. Holding a 63° field across a 2x zoom range keeps the framing familiar as magnification changes, and parfocal behaviour means the image stays close to focus while you move between settings. The long eye relief comes from the eyepiece's optical layout, so the full field is visible from behind eyeglasses.

Recommended Uses

• Planetary and lunar observing: zoom in and out with the seeing to find the sharpest magnification.
• Double stars and clusters at medium to high power.
• Daytime spotting-scope use: SVBONY lists the SA401 APO and SV406P spotting scopes as compatible.

Compatibility and Accessory Notes

• Focusers and diagonals: fits 1.25″ and 2″ eyepiece holders; the 2″ lens interface is included.
• Filters: M28.5 x 0.6 thread on the 1.25″ barrel, M48 x 0.75 on the 2″ barrel.
• Spotting scopes: SVBONY lists the SA401 APO and SV406P; the SA406 eyepiece adapter connects the SA401 to the SV245.
• Astigmatism correctors: mainstream correctors can be installed.

What's in the Box

• 1 x SVBONY SV245 8–16 mm zoom eyepiece
• 1 x 2″ lens interface
• 3 x Dust caps
• 1 x Eyepiece soft bag

Good to Know Before You Order

• Weight: at 486 g it is heavier than most fixed eyepieces, which is worth accounting for in balance on a small mount.
• Outer diameter: 60 mm, so it suits diagonals and focusers that clear a 60 mm body.
• Exit pupil: focal length and magnification depend on your telescope; get in touch if you want us to work out the range for your scope.

Frequently Asked Questions

Is it difficult to set up?

No. It drops into a 1.25″ holder directly or into a 2″ holder with the included interface, and you zoom by turning the barrel between click stops.

Do I need to refocus when zooming?

Very little. SVBONY specifies the SV245 as parfocal, so only small focus touch-ups are typical.

Can I use it with glasses?

Yes. Eye relief is 17–18 mm and the eye guard folds down for glasses wearers.

How does it compare with the SV230?

SVBONY publishes the SV245 at 8–16 mm with a 63° field, 8 elements in 5 groups and 486 g; the SV230 covers 8–20 mm with a 57–72° field, 9 elements in 6 groups and 500 g.

Bottom Line

In short: an 8–16 mm, 63° zoom eyepiece with click stops, parfocal operation, 17–18 mm eye relief and a dual 1.25″/2″ barrel, suited to high-power planetary and lunar observing.