Tele Vue 2x Barlow 1.25-inch — image 1
Tele Vue

Tele Vue 2x Barlow 1.25-inch

2× · 1.25" · fully multi-coated

Doubles the magnification of any 1.25" eyepiece, turning a two-eyepiece kit into four useful powers, with Tele Vue optics that add no visible softness.

87/ 100
Polaris Score
The premium pick among the barlows we recommend
From$153
Where to buy
Affiliate link — we earn a commission, you pay the same. We rank on fit, not payout.
What problem does this solve?

One Barlow doubles every eyepiece you own.

A Barlow is a negative lens that sits between your eyepiece and the telescope and multiplies the magnification, a 2× Barlow makes a 20 mm eyepiece perform like a 10 mm one. Drop it in front of each eyepiece in your case and you effectively double the number of powers you can reach without buying more glass.

The catch with cheap Barlows is that they trade sharpness for reach: they add colour, dim the view, or soften the edges. The Tele Vue is the reference 2×, its figure and coatings are good enough that the doubled view looks like it came from a shorter eyepiece, not from an add-on.

You need one if
You need one if you have two or three eyepieces and want more high-power options for the Moon, planets and double stars without buying a whole new set.
You can skip it if
You can skip it if you already own a dense ladder of short eyepieces, or observe mostly wide-field deep-sky where extra magnification just dims the target.
How it actually works

What the setup looks like.

A Barlow drops into the light path ahead of the eyepiece. The order matters, and so does where you place it relative to a star diagonal.

A Barlow drops into the light path ahead of the eyepiece. The order matters, and so does where you place it relative to a star diagonal.

1
Pull the eyepiece
Take the eyepiece out of the focuser or diagonal and set it aside. Nothing else in the setup has to change.
2
Drop the Barlow in
The 1.25 inch nosepiece goes into the focuser or diagonal exactly where the eyepiece was sitting. Tighten the thumbscrew.
3
Seat the eyepiece on top
The eyepiece now goes into the top of the Barlow. Any 1.25 inch eyepiece fits, whatever the brand.
4
Refocus outward
Inserting the Barlow shifts the focus point, usually by a noticeable turn of the knob. Refind focus before judging the view.
5
Thread filters onto the nose
The filter thread on the Barlow nosepiece lets a Moon or colour filter stay in the train while you swap eyepieces above it.

Placing the Barlow ahead of a star diagonal rather than directly under the eyepiece raises the amplification above 2x, because the added path length increases the factor. Start with it directly under the eyepiece so you always know the power you are observing at.

01Will it fit my setup

Compatibility.

What this accessory works with — check the fit before you check the price.

What this accessory works with — check the fit before you check the price.

1.25" focusersAny 1.25" eyepieceRefractorsNewtonians & DobsSCTs & Maks
Note✕Not for 2" eyepieces✕Adds one more optical group
02The numbers

What These Numbers Mean

4 numbers in plain English · full specifications

4 numbers in plain English · full specifications

Magnification factorDoubles power
2x
Halves the effective focal length of any eyepiece you use with it, so a 24 mm behaves like a 12 mm while retaining the 24 mm's comfortable eye relief. It effectively doubles the size of your eyepiece case.
Optical qualityReference
Fully corrected achromatic
Tele Vue Barlows are corrected well enough that they do not visibly soften the view at high power, which is the failure mode of budget Barlows. You can use it with premium eyepieces without giving anything back.
Barrel sizeStandard
1.25 inch
Fits the standard focuser and diagonal size found on nearly every telescope, and works with any 1.25 inch eyepiece regardless of brand.
Where it helps mostHigh power
Planets, the Moon, doubles
Magnification is what those targets reward. On faint galaxies and nebulae, doubling the power spreads the same light over four times the area, so lower power usually shows more.
Optical
TypeBarlow, negative lens
Amplification2×
Fit1.25" barrel
CoatingsFully multi-coated
EffectHalves any eyepiece's focal length
In use
BodyMachined, anodised aluminium
Best onMoon · planets · double stars
Pairs withYour mid- and long-focal eyepieces
AddsOne extra air-glass group
03Before you buy

Good to know.

The honest caveats — the things that save you a return, a bad first night, or a second purchase you didn't need.

The honest caveats — the things that save you a return, a bad first night, or a second purchase you didn't need.

It multiplies power, not aperture.
A Barlow can't show more than your aperture resolves, past roughly 50× per inch the image just gets dim and soft. Use it to fill gaps in your power range, not to chase empty magnification.
Barlow your comfortable eyepieces.
The Barlow inherits the eye relief of whatever eyepiece you pair it with, so a long, relaxed eyepiece plus this Barlow gives high power without the pinhole squint of a short eyepiece.
Start at the nominal 2×.
Dropped straight into the focuser it gives about 2×; adding spacing raises the factor. Begin at the marked 2× and you always know exactly what power you are observing at.
Editor’s Take

Ask a long time observer which accessory they would replace last and this one comes up more often than any eyepiece. It is the piece of glass that quietly ended a decades long argument about whether a Barlow costs you sharpness, and for most observers the answer became no. Decades on it is still in the case, still working, still the thing you hand a beginner to show what good glass is actually worth.

— The Skynocular verdict
87/ 100
Tele Vue 2x Barlow 1.25-inch
2× · 1.25" · fully multi-coated · $153

Doubles the magnification of any 1.25" eyepiece, turning a two-eyepiece kit into four useful powers, with Tele Vue optics that add no visible softness.