SVBONY SV136 1.25″ 3x Barlow Lens

Product Overview

The SVBONY SV136 (item F9172C) is a 1.25″ 3x achromatic Barlow lens. It triples the effective focal length of your telescope, and with it the magnification of any 1.25″ eyepiece placed in it. The optics are three elements in two groups with multilayer broadband coatings, in a two-step anodized aluminium body with a matte finish. End caps and an eyepiece set screw are part of the design.

Who It's For

This is a good match if you observe with 1.25″ eyepieces and want planetary and lunar magnifications without buying very short focal-length eyepieces — especially on fast, short-focal-length telescopes, which SVBONY designed it for.

Key Features & Design

• 3x magnification: a 15 mm eyepiece behaves like a 5 mm.
• Achromatic 3-element / 2-group design: colour-corrected to keep chromatic aberration low.
• Fully multi-coated: multilayer HD broadband green coatings.
• Two-step anodized aluminium body: matte finish against reflections and glare.
• End caps and set screw: dust protection and a secure eyepiece hold.

Optical Design

A Barlow is a negative lens group ahead of the focal plane that lengthens the effective focal length. The SV136 uses an achromatic three-element, two-group design to multiply focal length by three while keeping colour fringing in check, which matters most on fast telescopes where a simple Barlow would show more false colour.

Recommended Uses

• Planetary observing: Jupiter, Saturn and Mars at high power.
• Lunar detail along the terminator.
• Double stars.

Compatibility and Accessory Notes

• Eyepieces: SVBONY states it fits most 1.25″ eyepieces, including Celestron and Orion.
• Focuser: inserts into a 1.25″ focuser or diagonal.

Good to Know Before You Order

• Useful magnification has a ceiling: aperture and seeing set it, so a 3x Barlow pairs best with medium and longer eyepieces.
• 1.25″ only.
• Weight: not published by SVBONY.

Frequently Asked Questions

Is it difficult to set up?

No. Insert the Barlow into your focuser or diagonal, place the eyepiece in it, tighten the set screw and refocus.

Which eyepieces work best with it?

Medium to long focal lengths — roughly 12 mm to 25 mm — reach planetary magnifications with comfortable eye relief.

Why 3x rather than 2x?

On fast, short-focal-length telescopes, 3x reaches high planetary powers that a 2x Barlow would need very short eyepieces to match.

Bottom Line

In short: a 1.25″ achromatic 3x Barlow with fully multi-coated 3-element optics, made to give fast telescopes planetary magnifications with the eyepieces you already have.