SVBONY SV48P 102mm f/6.5 Achromatic Refractor Telescope OTA with 2.5″ Dual-Speed Focuser

Product Overview

The SVBONY SV48P 102 is a 102 mm achromatic refractor optical tube with a 663 mm focal length at f/6.5. It uses an air-spaced doublet objective with full multi-coating, a 2.5″ rack-and-pinion dual-speed focuser with 1:10 fine focus and millimetre markings on the drawtube, and integral tube rings on a 210 mm dovetail plate.

The focuser takes 2″ accessories directly and 1.25″ accessories through the supplied adapter. The OTA weighs 3400 g and measures 720 × 270 × 230 mm.

Who It's For

This is a good match if you:

• Want a bright, wide-field visual refractor: 102 mm at f/6.5 frames star clusters, the Moon and larger nebulae with low-power eyepieces.
• Observe the Moon and planets too: with the SV231 correction filter, SVBONY's recommended pairing, colour fringing on bright targets is reduced.
• Want room to grow: the 2.5″ focuser and 2″ eyepiece support take wide-field eyepieces and heavier diagonals.
• Are choosing a first serious telescope: a refractor needs no collimation and is ready as soon as it is mounted.

Key Features & Design

• 102 mm air-spaced achromatic doublet: fully multi-coated (FMC) for light transmission and contrast.
• 663 mm focal length, f/6.5: a middle ground between fast wide-field and slow high-power refractors.
• 2.5″ rack-and-pinion dual-speed focuser: coarse focus plus 1:10 fine focus, with millimetre markings on the drawtube.
• Light-leak control: SVBONY designs the tube to reduce light leakage for a clearer view.
• Integral tube rings on a 210 mm dovetail: holds the tube stable and the optics aligned.
• Finder bracket: dovetail slots for a finder scope.

Optical Design

The SV48P uses a two-element, air-spaced achromatic objective. An achromat brings two wavelengths to a common focus, which gives sharp, high-contrast views across most of the visible spectrum; at f/6.5 a faint violet fringe can show around the brightest objects such as the Moon's limb, Venus and Jupiter. SVBONY's SV231 chromatic aberration correction filter is designed to reduce that fringe.

The f/6.5 focal ratio sits between fast f/4–f/5 instruments and slow f/11–f/15 instruments, giving a wider, brighter field than a long-focus refractor while keeping enough focal length for the Moon and planets. Full multi-coating on the lens surfaces keeps colours natural and the background dark.

Recommended Uses

• Wide-field visual observing: open clusters, the Pleiades, the Double Cluster and bright nebulae.
• Lunar and planetary viewing: the Moon, Jupiter and Saturn at moderate magnification, best with the SV231 filter.
• Nebulae and galaxies: SVBONY positions the f/6.5 ratio for brighter views of extended objects.
• Daytime terrestrial viewing: with an erecting diagonal.

Compatibility and Accessory Notes

• Eyepieces: 2″ directly, 1.25″ through the supplied adapter.
• Visual set-up: SVBONY describes using the SV48P with a diagonal, eyepiece and finder scope; none of these are included with the OTA.
• Colour correction: the SVBONY SV231 correction filter is SVBONY's recommended companion for bright targets.
• Mounting: 210 mm dovetail plate on integral rings. At 3400 g the OTA suits a sturdy alt-az or small equatorial mount.
• Focuser rotation: the focuser is not 360° rotatable.

What's in the Box

• 102 mm f/6.5 telescope OTA
• 210 mm dovetail mounting plate with tube rings
• Finder scope dovetail slots
• 2″ to 1.25″ adapter
• Lens cover
• 1.25″ dust cover

Good to Know Before You Order

• Optical tube only: no mount, tripod, diagonal, eyepiece or finder is included. SVBONY also offers the SV48P 102 in visual sets with these accessories.
• Achromatic optics: some false colour shows on the brightest targets at f/6.5; the SV231 filter reduces it.
• Visual first: the SV48P 102 is designed and described by SVBONY for visual observing.
• Dew: a dew heater strip around the lens cell keeps the objective clear on humid nights.

Frequently Asked Questions

Is it difficult to set up?

No. The dovetail on the integral rings drops into the mount saddle, and a diagonal and eyepiece complete it. A refractor needs no collimation.

Does it take 2″ eyepieces?

Yes. The 2.5″ focuser accepts 2″ accessories directly, and the supplied adapter takes 1.25″ eyepieces.

What is the fine-focus ratio?

1:10, on a rack-and-pinion focuser with millimetre markings.

How much does it weigh?

3400 g for the OTA.

Will I see false colour?

On the brightest objects a faint fringe is normal for an f/6.5 achromat; SVBONY pairs the SV48P with its SV231 correction filter to reduce it.

Bottom Line

In short: a 102 mm f/6.5 air-spaced achromatic refractor with a 2.5″ dual-speed focuser, integral rings and a 210 mm dovetail, weighing 3400 g. Add a mount, a diagonal and eyepieces for bright, wide-field visual observing.