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GSO 1.25" 2x "Shorty" Achromatic Barlow Lens # GS2BL

4.7 (57 Reviews) Read Reviews Write Review
Brand GSO
Part Number GS2BL
Availability available

Product Info

Manufacturer Description

GSO's 1.25" 2x "Shorty" achromatic Barlow is an excellent accessory that allows you to effectively double the number of eyepieces in your collection. This barlow uses two-element, fully-multicoated lenses with excellent color correction and sharpness. The lens edges are blackened to maximize image contrast. The body is precision CNC-machined from aluminum and sports a handsome finish.

A really nice feature of this GSO barlow is that the barlow element is housed in a separate metal cell at the bottom that can be unscrewed from the upper tube (see photos). You can then screw the barlow cell directly into 1.25" eyepieces with a standard 1.25" filter thread to increase the magnification of that particular eyepiece while still maintaining a low profile. When screwed into an eyepiece, the barlow will yield approximately 1.5x of magnification. So, for example, a 30mm eyepiece can be used with the barlow element screwed on as a 20mm eyepiece, or with the complete barlow as a 15mm eyepiece. That's like having three eyepieces in one! You can also use the tube by itself without the barlow element as a 36mm (1.4") extension tube for 1.25" eyepieces and accessories.

Note that the use of any optical element like barlows and focal reducers changes the focus point of your telescope, requiring additional in-focus or out-focus travel. The exact amount of focus travel required will depend on the optics and mechanics of your specific set-up (telescope, diagonal (if used), barlow, and eyepiece). Hence, be aware that you may not be able to reach focus with all eyepieces or in all configurations with a given barlow.

Specifications:

  • Barrel Size: 1.25 inch (31.7mm)
  • Magnification Factor: 2x
  • Type: Achromatic
  • Coatings: Fully multicoated, Blackened lens edges
  • Weight: 3.3oz
  • Height (Total): 78mm
  • End Caps: 2
  • 1.25" filter threads on bottom of barlow: No
  • Made in Taiwan

Reviews

4.7 (Based on 57 Reviews) 96% of reviewers recommended this product.
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    1. Guest

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      Review by Rafael L.
      1516080721
      Jan 15, 2018

      5.0 GSO 1.25" 2x "Shorty" Achromatic Barlow Lens # GS2BL fr

      Pros:

      Cons:

      Comments:

      Works as expected.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    2. Guest

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      Review by Man N.
      1515119514
      Jan 4, 2018

      5.0 It does what it is intended for

      Pros:

      Cons:

      Comments:

      It's cheap and it works well.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    3. Guest

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      Review by Chad B.
      1506356093
      Sep 25, 2017

      4.0 Worth it for the price

      Pros:

      Cons:

      Comments:

      A little on the cheap side due to plastic feel but at the price point it's perfect for newcomers like myself. The dual zoom levels are a nice feature as well.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    4. Guest

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      Review by James D.
      1504705340
      Sep 6, 2017

      5.0 Excellent value

      Pros:

      Cons:

      Comments:

      Clear image quality. Couples perfectly between my Canon 60D with 1.25" adapter and the back of the Celestron 6SE.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    5. Guest

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      Review by Victor L.
      1504291694
      Sep 1, 2017

      5.0 Great optics

      Pros:

      Cons:

      Comments:

      Works as it should.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    6. Guest

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      Review by David A.
      1498864886
      Jun 30, 2017

      5.0 Great Barlow

      Pros:

      Cons:

      Comments:

      Great Barlow

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    7. Guest

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      Review by Kent R.
      1498644539
      Jun 28, 2017

      5.0 Well Crafted

      Pros:

      Cons:

      Comments:

      The GSO 2x Barlow lens is machined very nicely, gives off a high quality appearance, and light in weight.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    8. Guest

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      Review by Cahit Ü.
      1483119664
      Dec 30, 2016

      5.0 A barlow better than i expected!

      Pros:

      Cons:

      Comments:

      It's a quality product which has a high price-performance ratio. The lens which has removable feature is an advantage. I used it with various eyepieces and I got a good result. Its the only fault is that its box is cheap.

      Location: Turkey

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    9. Paul Schofield

      Paul Schofield New Member

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      Review by Schweitzer of Hollywood, FL.
      1476144000
      Oct 10, 2016

      4.0 Two barlows in one

      Pros:

      Lightweight,Accurate,Compact,Strong Construction,Easy to Use,Quality Lenses

      Cons:

      Comments:

      This is a lightweight well made barlow that can be used in the 1.5x or 2.0x mode. This gives you flexibility with your eyepieces but it involves unscrewing the barlow lens and attaching it to the bottom of the eyepiece. This can get a bit problematic in the dark. I found the quality of the image quite good in the 2x mode but not quite as good in the 1.5x mode. And the images in my older long 3x barlow were just a bit better than the performance of this shorty in either mode. I know I'm being picky but the longer barlows give better results. Still, it will give good results, especially considering the price. And because of its size it will work well in the diagonal of smaller scopes like refractors, sct's, and maks.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    10. Dr. Ski

      Dr. Ski Well-Known Member

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      Review by Dr. Ski of Obscure Philippine Island.
      1445472000
      Oct 21, 2015

      5.0 I'm really starting to love GSO

      Pros:

      Compact,Lightweight,Strong Construction,Quality Lenses,Easy to Use

      Cons:

      Comments:

      Most barlows have removable lens housings, but GSO is one of the few manufacturers to actually flaunt that. This is a great accessory for the price! This barlow does not exacerbate CA and even with a 40mm EP, eye placement is not critical! A little edge distortion? So what? If you're like me, you like to place objects in the centre of the field! Even when I use averted vision, I seldom reach the edge of the field. Want a wider field? Use a lower power! This barlow gives you lots of FOV options. I love it.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    11. Guest

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      Review by The Wrong Solution of Los Angeles.
      1435363200
      Jun 26, 2015

      4.0 Great affordable barlow

      Pros:

      Strong Construction,Lightweight,Easy to Use

      Cons:

      Chromatic aberration

      Comments:

      This is a decent barlow lens for its price. I originally purchased this barlow mainly to extend the focal length of my telescope (I have an f/5 reflector) for mounting my DSLR. Overall, I am satisfied with my purchase. I ended up using the barlow more for visual observing rather than photography. The neat thing about this barlow is that you can unscrew the bottom of it and attach that to your eyepiece for a lower magnification. This comes in handy when the atmosphere isn't cooperating.

      The downside of this barlow is that even though it is achromatic, it still suffers from a bit of chromatic aberration, especially when looking at bright objects like Venus.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    12. Saguaro

      Saguaro New Member

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      Review by saguaro of Tucson, AZ.
      1424476800
      Feb 20, 2015

      5.0 Excellent quality

      Pros:

      High Quality Optics,Easy to Use,Quality Lenses

      Cons:

      Comments:

      I use this as a 1.5x barlow by using only the lens with my Skyris 132m camera's nosepiece. It allows me to get higher magnification for solar imaging. I also screw the lens into my eyepiece to increase the magnification. Great quality and versatile.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    13. Steve

      Steve New Member

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      Review by Steve of Pennsburg, PA.
      1417996800
      Dec 7, 2014

      5.0 Almost as good as my ES

      Pros:

      Strong Construction,Easy to Use,Lightweight,Quality Lenses

      Cons:

      Comments:

      Bought this for a new astronomer in the family. Before I give it to him, I tried it out on my ETX60 and 130SLT with my 25mm plossl. Used it on the moon and M42 and compared it against my ES 2X. This barlow stacked up well against the ES, had SMALL amount viginetting compared to the ES and I had to really look for it. About 1/3 the weight and 1/4 the price.
      Gave it 5 stars because you can't beat the price/value.
      Also like the idea of screwing the bottom element to an eyepiece. If you have a limited budget, you can triple the amount of eyepieces for very little money

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    14. Guest

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      Review by GeorgeT of New York.
      1410998400
      Sep 17, 2014

      5.0 Worth its weight in gold!

      Pros:

      Lightweight,Accurate,Quality Lenses,Easy to Use,Strong Construction,Compact

      Cons:

      Comments:

      Over the years I've purchased three of them from Agena for my Coronado 60mm SM, 10" f/6.3 Newt and to turn my Pentax XLs 7mm and 5.2mm into a 4.66mm and a 3.46mm respectively when the barlow element is used without the housing for 1.5X. The last configuration has saved me a lot of money as I didn't have to buy a Pentax XW 3.5mm and a Delos 4.5mm.

      There is no image breakdown, takes up no space in the eyepiece case and it's very inexpensive.

      In short, best accessory ever bought!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    15. Guest

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      Review by slingnasty of Alabama.
      1410048000
      Sep 6, 2014

      5.0 If I buy Telscope products it is from here

      Pros:

      Easy to Use,Quality Lenses,Lightweight,Compact,Accurate,Strong Construction

      Cons:

      Comments:

      It's a great product for sun looking moon watching everything that has to do with the stars, it makes me want to stand on my head and count greasy bb,s in alphabet order :)

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    16. Guest

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      Review by atgreen of Goleta, CA.
      1402790400
      Jun 14, 2014

      5.0 Great for the price

      Pros:

      Quality Lenses,Easy to Use

      Cons:

      Comments:

      I've used it for a few months. For the price it can't be beat. Good clear aperture diameter, coatings look good, no apparent degradation of eyepieces. I've always had good service from Agena.

      Bottom Line: Would you recommend this item? No
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    17. Guest

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      Review by jetmech of Clearwater, Fl.
      1401494400
      May 30, 2014

      5.0 Works as advertised

      Pros:

      Accurate

      Cons:

      Heavy

      Comments:

      Works so much better than the cheap barlows that come with telescopes or eyepiece combos - world of difference! (no pun). Amazing!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    18. gazer

      gazer New Member

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      Review by Seppo Kouva of Vanersborg Sweden.
      1392422400
      Feb 14, 2014

      4.0 Top Barlow for less money

      Pros:

      Quality Lenses,Compact,Strong Construction,Easy to Use,Lightweight,Dual Barlow,Accurate

      Cons:

      No Brass Ring

      Comments:

      My favorite Barlow! If you don`t need 2x magnification, you can screw the barlow cell directly into 1.25" eyepiece and get 1. 5x of magnification. e.g If you have big bulky eyepices like Celestrons Ultima LX as I have or similar, you can screw the Barlow cell, to get the little extra magnification.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    19. Guest

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      Review by AZDaveC of Tucson, AZ.
      1380412800
      Sep 28, 2013

      5.0 Excellent quality

      Pros:

      Strong Construction,Quality Lenses

      Cons:

      Comments:

      Excellent build quality and flawless performance...and for a great price.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    20. Guest

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      Review by TonyB of Florida.
      1370822400
      Jun 9, 2013

      4.0 Very good product at a very good price

      Pros:

      Quality Lenses,Easy to Use

      Cons:

      Quality Lenses,Easy to Use

      Comments:

      Like others are saying, this is a good quality barlow at a good price. I'm happy with the quality and I tend to leave it in all the time as I feel that 2x view is better then using the 90MM telescope without it. Seeing the rings of Saturn is very cool!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    21. Guest

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      Review by Grego of Sao Paulo, Brazil.
      1364169600
      Mar 24, 2013

      3.0 Good but not best

      Pros:

      Strong Construction,Easy to Use

      Cons:

      Difficult To Focus,Poor Lens Quality

      Comments:

      Great item, low price, good quality, but nothing compared to high-end products.
      I recommend it anyway, the price versus quality is really great!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    22. Irakli

      Irakli New Member

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      Review by Thunder of Tbilisi, Georgia.
      1364083200
      Mar 23, 2013

      5.0 Brilliant Barlow Lens

      Pros:

      Lightweight,Compact,Strong Construction,Quality Lenses,Accurate

      Cons:

      Comments:

      Best barlow lens I ever had. No picture degrading, no false color and best price in this range. Agenaastro delivered it very soon. Now looking to buy X3 GSO ED barlow.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    23. Guest

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      Review by Frugal Astronomer of Boston, MA.
      1363996800
      Mar 22, 2013

      4.0 Great price/performance

      Pros:

      Easy to Use,Versatile,Lightweight,Quality Lenses

      Cons:

      Comments:

      This is an inexpensive 2x barlow with a great price/performance ratio. High quality optics with a versatile design.

      I like that you can unscrew the barlow lens and attach directly to the filter threads on your 1.25" eyepieces, which makes for a cost effective way to stretch a limited eyepice collection even further. NOTE: You may not have sufficient focus travel in this configuration -- this can be remedied any one of a number of ways. I just move the EP out a little, but I could also back out the 2" adapter in my focuser if I so chose. This allows me to use the 2x barlow on my 11mm EP (109x mag in my scope) to obtain 218x. If I find that is a bit too much for that night's seeing, I can attach the barlow lens directly to the EP for an approximate 1.5x mag, yielding a much more commonly usable 163x (approx.). There are very many nights that the 1.5x sees use, making this a valuable feature to have.

      I more recently acquired a 6.7mm EP that, natively, yields approximately 179x in my scope. I've compared my 11mm + barlow lens, at approx 163x and found that, other than the minor magnification difference, the visual quality is relatively indiscernible. This gives me confidence to use the barlow in both the 2x and 1.5x configurations, matching the magnification to what is best for any given night, if I'm looking to push the power beyond what my EP's can do on their own.

      If I had to knock this product at all, it would be the overall build quality. It's not built like a tank. It's a lightweight tube with some glass. The barlow lens 'squeaks' when being unscrewed/screwed. The horror. For the cost, these aren't fair nits to pick. I gladly accept these in exchange for the excellent optical performance at a remarkably low cost.

      Overall, I'm very happy with this inexpensive barlow and I would buy another without hesitation, should I ever need to.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    24. Guest

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      Review by tnranger of Southeast.
      1363996800
      Mar 22, 2013

      4.0 A good buy!

      Pros:

      Strong Construction,Lightweight,Compact,Easy to Use

      Cons:

      Comments:

      Came highly recommended on Cloudy Nights Forums, with good reason. Well made, works well.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    25. Guest

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      Review by Astro Jo of Australia.
      1360540800
      Feb 10, 2013

      4.0 I would buy this product again

      Pros:

      Easy to Use,Strong Construction,Quality Lenses,Lightweight,Accurate

      Cons:

      Comments:

      I use this on a telescope and it provides sharp stars across 90% of the field of view. Mutch better than I expected for the price. I recommend it for any body.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    26. Guest

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      Review by Another Bruce of Claremont, CA.
      1360368000
      Feb 8, 2013

      5.0 Great Value

      Pros:

      Versatile,Strong Construction

      Cons:

      Comments:

      So far I've used this for Sun and Planet viewing, and the views are great. I find I use the detachable lens for 1.5 magnification more than I use the complete barlow. The versatility is great. Most barlows double your eyepiece collection. This one triples it.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    27. Guest

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      Review by AntMan of NY.
      1348272000
      Sep 21, 2012

      5.0 This ain't you regular 2x Barlow

      Pros:

      Strong Construction,Accurate,Lightweight,Quality Lenses,Easy to Use

      Cons:

      Comments:

      This baby lets you downgrade to 1.5X on nights that don't allow you to use 2X on your high power or favorite eyepiece. It's 2 Barlow lenses in one, unscrew the base lens and just screw that into the bottom of your eyepiece and your at 1.5 instead of 2. It is like having three Delos eyepieces without paying for three! Best solution to a Barlow ever invented!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    28. Guest

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      Review by Chris of Newport News, VA.
      1348272000
      Sep 21, 2012

      5.0 Great barlow

      Pros:

      Easy to Use,Lightweight,Strong Construction

      Cons:

      Comments:

      This barlow comes highly recommended on several astronomy forums, and I see why. This is a great barlow, and I especially like that you can remove the endpiece and thread it onto an eyepiece for 1.5x

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    29. Guest

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      Review by Jamie of Tennessee.
      1335744000
      Apr 29, 2012

      5.0 Best Barlow out there

      Pros:

      Strong Construction,Multi uses,Functionality,Quality Lenses

      Cons:

      Comments:

      This is the best Barlow out there. Not only does it funtion perfectly as a 2x Barlow providing views with clarity and sharpness, but the bottom lens cell can be used alone as a 1.5x Barlow. I actually use the lens cell alone more than I do the entire assembly. A great product at prices you can afford, that's usually the case with Agena Astro.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    30. Guest

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      Review by New guy of Texas.
      1330300800
      Feb 26, 2012

      5.0 Great Quality and Design

      Pros:

      Strong Construction,Versatile

      Cons:

      None

      Comments:

      Easy to use, fantastic value, would recommend to anyone wanting to triple their eyepieces at a low cost.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    31. philippelletier

      philippelletier New Member

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      Review by Philip of Raleigh, NC.
      1330128000
      Feb 24, 2012

      5.0 GSO 1.25" 2x Achromatic Barlow Lens

      Pros:

      Strong Construction,Lightweight,Quality Lenses,Accurate,Compact,Easy to Use

      Cons:

      Comments:

      Lightweight, well constructed, clever design with the removable lens for 1.5x or 1.6X. Like any good Barlow, you don't really know it is there. Only drawback is it uses a set screw rather than a compression ring. Should at least come with an nylon set screw along with the metal one. Excellent value!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    32. Guest

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      Review by Chimico Pazzo of Bologna, Italy.
      1323129600
      Dec 5, 2011

      4.0 One of the best cheap barlow, almost APO

      Pros:

      Strong Construction,Quality Lenses,Easy to Use,Lightweight

      Cons:

      Comments:

      I am sorry for my English...

      It is a very usable barlow: like 2x, like about 1,5x and like corrector for binoviewer about 2,6X.
      With only one object I have tripled my eyepieces! I have found a very good chromatic correction.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    33. Guest

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      Review by Andy of Calgary, AB.
      1320624000
      Nov 6, 2011

      5.0 Best bang for the $$$

      Pros:

      Strong Construction,Quality Lenses,Easy to Use

      Cons:

      Comments:

      Great barlow. Love the fact it can be a 2x or 1.5x barlow. Like others, I find I screw the lens onto my eyepieces more than using it as a 2x. No issues viewing with this. The 2" will be next.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    34. Guest

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      Review by Sprang of Milky Way.
      1311984000
      Jul 29, 2011

      5.0 Better than expected!

      Pros:

      Accurate

      Cons:

      Comments:

      Great quality Barlow! I use it in combination with a 25mm @ 10 mm on a fast 5.9 1200mm Dobsonian and can tell you for the money Its impossible to beat.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    35. Guest

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      Review by RJ of Australia.
      1306972800
      Jun 1, 2011

      4.0 Great Affordable Barlow.

      Pros:

      Strong Construction,Accurate,Quality Lenses

      Cons:

      None

      Comments:

      I bought the barlow to increase the magnification of other GSO eyepieces I bought from Agena Astro, and it works like a charm. I'm very pleased with it and that there is no dimming of the image when used with an eyepiece. My set is now larger thanks to this awesome inexpensive barlow. Highly recommend.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    36. chromesphere

      chromesphere New Member

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      1306966680
      Jun 1, 2011

      5.0 A great budget barlow!

      Pros:

      Image Quality, Construction, Removable Lens, Cost

      Cons:

      none!

      Comments:

      I was looking for a decent quality barlow at a budget price. After searching many reviews, I ended up deciding on this one. It's a transparent lens. I cannot detect any degradation in image quality at all.

      The removable lens element is a great feature. You can stack this lens on top of your existing filters for 1.5x magnification (approx). This is great for when 2x is pushing the magnification too far. It gives you more options. And also, using a heavy wide angle EP with a barlow can make your configuration a little worrying. Using the removable lens doesn't increase the length of the stack.

      The construction was also surprising. I was quite shocked to see that the entire EP was made from aluminium, no plastic. I honestly thought at this price there was be some cheap components but the whole product looks pretty solid.

      If you're looking for a budget barlow, this is a good one!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No
    37. chromesphere

      chromesphere New Member

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      Review by chromesphere of Melbourne, Australia.
      1306886400
      May 31, 2011

      5.0 A great budget barlow!

      Pros:

      Strong Construction,Quality Lenses,Accurate,Compact

      Cons:

      Comments:

      I wasnt expecting much from this barlow. Something of decent quality. The barlow is very tranparent. I can not see any degradation of the image through my set up. The removable bottom lens isnt a gimmick, its a very useful feature. Infact I use the bottom lens (stacked on top of my filters) more then the complete barlow!
      If your after a good barlow, and you dont want to spend hundreds, give this one a try!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    38. Guest

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      Review by Theodoros of Athens, Greece.
      1303948800
      Apr 27, 2011

      5.0 Excellent product, 2 in 1

      Pros:

      Accurate,Compact,Quality Lenses,Strong Construction

      Cons:

      Comments:

      Excellent product from GSO. Love the fact that I can use 2 in 1 with top quality for the money spent!

      I mostly used the barlow lens cell with a big FOV EP and the images were sharp and clear!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    39. Guest

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      Review by star gazer of Albany, NY.
      1294531200
      Jan 8, 2011

      5.0 Well made product at a good price

      Pros:

      No

      Cons:

      No

      Comments:

      I researched a number of Barlows and this one had good reviews and a great price. I found it to be well made. The tolerances were tight. No play at all. Optics were fine.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    40. Guest

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      Review by The refractor guy of Elgin IL.
      1294444800
      Jan 7, 2011

      5.0 Great Barlow

      Pros:

      Compact,Accurate,Strong Construction,Quality Lenses

      Cons:

      Comments:

      Super barlow for the money. Very nice coatings super sharp images.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    41. Guest

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      Review by FRANKB of Parma Heights, Ohio.
      1294272000
      Jan 5, 2011

      5.0 Quality Barlow, Low Price

      Pros:

      Accurate,Quality Lenses,Strong Construction

      Cons:

      Comments:

      This is not a cheap barlow, it is very well made, with good optics. Very good quality for low price,highly recommended.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    42. Guest

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      Review by Mat of Halifax, NS.
      1294099200
      Jan 3, 2011

      5.0 Great barlow

      Pros:

      Quality Lenses,Strong Construction,Accurate,Compact

      Cons:

      Comments:

      This barlow is simply great, I love the fact you can unscrew the lens and use on an EP and also use the tube as an extension tube if required.

      You won't regret buying this barlow.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    43. Guest

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      Review by James of Louisville, KY.
      1292803200
      Dec 19, 2010

      5.0 Excellent Barlow

      Pros:

      Good quality,No visible light loss

      Cons:

      None

      Comments:

      This is a very nice barlow lens. I have owned it for almost a year, and have been very pleased with the views. The only complaint I can think of is I would prefer a plastic set screw instead of metal.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    44. Guest

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      Review by Luti of Croatia.
      1292803200
      Dec 19, 2010

      4.0 I would buy this product again

      Pros:

      Strong Construction,Compact,Accurate

      Cons:

      Sensitive lens coating

      Comments:

      The great thing is that you can separate barlow in 2 pieces and use just lens for smaller magnification

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    45. Nubcaek

      Nubcaek New Member

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      Review by Herp Mc Derp of Bellflower, CA.
      1274227200
      May 18, 2010

      4.0 Good starter barlow

      Pros:

      Quality Lenses,Accurate,Compact,Strong Construction

      Cons:

      Comments:

      Cheap strong and easy to use I like how simple it is and you can use it as an extension tube if you remove the lens element.

      You get more than plenty for this barlows low price.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    46. mkamel26

      mkamel26 New Member

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      Review by Morris of Washington, DC.
      1266019200
      Feb 12, 2010

      4.0 Good low-cost barlow

      Pros:

      Quality Lenses,Strong Construction

      Cons:

      Comments:

      This is a good low-cost barlow. I unscrewed the lens part and screwed it on one of my other lenses, like a filter, and it definitely improved the image

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    47. Guest

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      Review by Prof. Clyde of Tampa Bay, Florida.
      1257724800
      Nov 8, 2009

      5.0 A great barlow lens

      Pros:

      Quality Lenses,Compact,Strong Construction,Accurate

      Cons:

      None

      Comments:

      Great product...highest quality construction...very compact.
      The removable lower lense can be used on any eyepiece or web type camera and the upper part makes a good extension tube when you need additional focuser travel.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    48. DSalters

      DSalters New Member

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      Review by DSalters of St. Louis, MO.
      1243987200
      Jun 2, 2009

      3.0 Convenient but Squeaky!

      Pros:

      Accurate,Convenient Feature

      Cons:

      Squeaky

      Comments:

      This is a barlow that is convenient for the purposes of unscrewing the lens assembly and rethreading it on an EP. Having this option is not something you can find with any barlow.

      The downside to this unscrewing is the squeaking! I ultimately sold this barlow for this reason. I couldn't take the squeaky noise it made when I did undid the lower elements.

      Pros: It worked fine and was convenient
      Con: High-pitched noise was too much for me

      Bottom Line: Would you recommend this item? No
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    49. Guest

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      Review by Bassman of Taylor, PA.
      1243468800
      May 27, 2009

      4.0 Excellent views without the high price

      Pros:

      Compact,Quality Lenses,Accurate,Strong Construction

      Cons:

      Comments:

      Works great in my spotting scope with low power eyepiece

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    50. TransPecosDob

      TransPecosDob New Member

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      Review by rekterx of Alpine, TX.
      1243382400
      May 26, 2009

      4.0 Great Barlow: Great Value

      Pros:

      Strong Construction,Accurate,Quality Lenses

      Cons:

      Comments:

      Great value! This barlow does exactly what it is supposed to do and it does it in a high quality package at a very reasonable cost. The feature which allows you to remove the barlow from the extension tube and attach it directly to the eyepiece has to be one of the most under appreciated options available to the beginning astronomer. This barlow turns one eyepiece into three!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    51. AstroGuy1

      AstroGuy1 New Member

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      Review by lenf of Texas.
      1243036800
      May 22, 2009

      5.0 Great Barlow!

      Pros:

      Great quality and price

      Cons:

      None at this point

      Comments:

      While I'm just building a starter set of eyepieces, optical quality is very important to me. I searched through a long list of possible barlow units, and this one is the best of the lot. The clarity and lack of internal reflection brings out the best in my eyepieces, and it provides a new range of magnification powers to my small collection.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    52. lenf

      lenf New Member

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      1239310080
      Apr 9, 2009

      5.0 Great Barlow!

      Pros:

      Great quality and price.

      Cons:

      None I can see at this point.

      Comments:

      While I'm just building a starter set of eyepieces, optical quality is very important to me. I searched through a long list of possible barlow units, and this one is the best of the lot. The clarity and lack of internal reflection brings out the best in my eyepieces, and it provides a new range of magnification powers to my small collection.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No
    53. Guest

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      Review by MtnGoat of Washington.
      1233619200
      Feb 2, 2009

      5.0 A fine product at a great price

      Pros:

      Perfect coatings,Very low price,Removable lens,Great piece of gear

      Cons:

      None that I can tell

      Comments:

      Having come of age back in the day when barlow was a dirty word, I was never particularly interested in revisiting this kind of accessory. In the mid 70's barlows promised big and never delivered, with dinky field lenses that looked like the 0.965 units they probably really were, slapped onto a 1.25 barrel and used anyway. I'd never look through a barlow that didn't kill contrast and sharpness, but at least in the process you got image vignetting as a bonus.

      Recently after changing jobs and moving to a dark sky site of my wildest dreams, the fire has rekindled and I've had the pleasure of dusting off the old 8" after over 20 years of storage, adding a Zhumell 12" dob to the lineup, and shopping for other reasonably priced modern accessories. I don't know what possessed me to give barlows another go, but I decided that given the excellent performance of the Z12 I'd try a modern barlow as well, being relatively inexpensive. I am glad I did.

      The GSO 1.25" was chosen due to the optical excellence I am discovering with the GSO made Zhumell dob. I figured that if they can turn out that kind of performance they must have some idea what they are doing, so I decided to risk with the GSO barlow and see if things have changed. Yes, they have, and for the better.

      The GSO 1.25 barlow is a well designed basic piece of gear. It has a large lens element instead of the tiny ones I remember, flawless coatings, a nicely machined barlow tube, and best of all, a removable cell for the lens itself which is standard threaded for any 1.25" eyepiece. This means you can simply unscrew it and put the lens directly on any eyepiece of this size, giving you an additional range of magnification.

      From what I can tell the 2x rating of the entire assembly is darn close to the 2x promised, and you can dial this back to about 1.6x by using the lens itself on the eyepiece. If you are using a refractor you can also go up from the 2x by placing it on the nose of the star diagonal, which appears to yield about 3x.

      I cannot tell much, if any, difference in image brightness when using this barlow other than the intrinsic amount caused by the higher magnifications. There is zero color fringing and no image vignetting either. This barlow not only cured me of my barlow prejudices, I actually find myself using it on purpose to go to higher mags while preserving most of the eye relief of the original longer FL eyepiece.

      I highly recommend this unit if you are in the market for a barlow. Now that I know I like it, I'm just biding my time until I can pick up one of the 2" ED barlows which also has a removable lens.

      From barlow hater to a guy who wants two of them is a testament to how well the GSO barlow in the 1.25" format works...it works great.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    54. Guest

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      Review by Steve of Florida.
      1232236800
      Jan 17, 2009

      5.0 Works for me!

      Pros:

      Comfortable Eyepiece,Quality Lenses,Accurate,Strong Construction

      Cons:

      Comments:

      I am very happy with the versatility of this barlow. The direct-screw-on option that basically can make every eyepiece you have get three different magnifications can't be beat, it's a great idea. I use it regularly (I in fact keep it in place when not using the scope because I rarely don't want to use it in one way or the other). I am a newbie to stargazing and this came highly recommended to me in an astronomy forum. I'm certainly glad I followed the advice and now recommend this barlow myself.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    55. melonman

      melonman New Member

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      Review by melonman of Minnesota.
      1227052800
      Nov 18, 2008

      5.0 GSO 1.25 inch 2X achromatic barlow

      Pros:

      Excellent buy,High quality

      Cons:

      None found

      Comments:

      I already had a fine Meade 2X "Telenegative" (barlow) in my case, so why get another 2x barlow? Well, because for its price you can get one that you can unscrew and fasten directly to your eyepieces and get somewhere like 1.6X to 1.8X. Thus, you get to have a lot more focal lengths. I really have found nothing wrong with this barlow. On eyepieces ranging from 7.5 mm plossls to 25mm and on wide fields to 70deg. Just as clear and sharp as my Meade.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    56. MtnGoat

      MtnGoat New Member

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      User Notes:
      1204157880
      Feb 27, 2008

      5.0 A fine product at a great price

      Pros:

      Removable lens, very low price, perfect coatings

      Cons:

      None that I can tell. This is a great piece of gear.

      Comments:

      Having come of age back in the day when barlow was a dirty word, I was never particularly interested in revisiting this kind of accessory. In the mid 70's barlows promised big and never delivered, with dinky field lenses that looked like the 0.965 units they probably really were, slapped onto a 1.25 barrel and used anyway. I'd never look through a barlow that didn't kill contrast and sharpness, but at least in the process you got image vignetting as a bonus.

      Recently after changing jobs and moving to a dark sky site of my wildest dreams, the fire has rekindled and I've had the pleasure of dusting off the old 8" after over 20 years of storage, adding a Zhumell 12" dob to the lineup, and shopping for other reasonably priced modern accessories. I don't know what possessed me to give barlows another go, but I decided that given the excellent performance of the Z12 I'd try a modern barlow as well, being relatively inexpensive. I am glad I did.

      The GSO 1.25" was chosen due to the optical excellence I am discovering with the GSO made Zhumell dob. I figured that if they can turn out that kind of performance they must have some idea what they are doing, so I decided to risk with the GSO barlow and see if things have changed. Yes, they have, and for the better.

      The GSO 1.25 barlow is a well designed basic piece of gear. It has a large lens element instead of the tiny ones I remember, flawless coatings, a nicely machined barlow tube, and best of all, a removable cell for the lens itself which is standard threaded for any 1.25" eyepiece. This means you can simply unscrew it and put the lens directly on any eyepiece of this size, giving you an additional range of magnification.

      From what I can tell the 2x rating of the entire assembly is darn close to the 2x promised, and you can dial this back to about 1.6x by using the lens itself on the eyepiece. If you are using a refractor you can also go up from the 2x by placing it on the nose of the star diagonal, which appears to yield about 3x.

      I cannot tell much, if any, difference in image brightness when using this barlow other than the intrinsic amount caused by the higher magnifications. There is zero color fringing and no image vignetting either. This barlow not only cured me of my barlow prejudices, I actually find myself using it on purpose to go to higher mags while preserving most of the eye relief of the original longer FL eyepiece.

      At 28 bucks currently I highly recommend this unit if you are in the market for a barlow. Now that I know I like it, I'm just biding my time until I can pick up one of the 2" ED barlows which also has a removable lens.

      From barlow hater to a guy who wants two of them is a testament to how well the GSO barlow in the 1.25" format works...it works great.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No
    57. melonman

      melonman New Member

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      User Notes:
      1167260400
      Dec 27, 2006

      5.0 The GSO 1.25 inch 2X achromatic barlow.

      Pros:

      Excellent buy, high quality

      Cons:

      none found for this item.

      Comments:

      I already had a fine Meade 2X "Telenagative" (barlow) in my case, so why get another 2x barlow? Well, because for only $25 you can get one that you can unscrew and fasten directly to your eyepieces and get somewhere like 1.6X to 1.8X. thus, you get to have a lot more focal lengths. I really have found nothing wrong with this barlow. On eyepieces ranging from 7.5 mm plossls to 25mm and on wide fields to 70deg. Just as clear and sharp as my Meade. Did I mention for 25 dollars which included shipping!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No
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      Specifications

      Manufacturer GSO