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Blue Fireball 2" to 1.25" Twist Lock Self Centering Eyepiece Adapter # E-11

4.7 (16 Reviews) Read Reviews Write Review
Brand Blue Fireball
Part Number E-11
Availability available

Product Info

Manufacturer Description

This popular eyepiece adapter allows 1.25" eyepieces and accessories to be used in 2" focusers, diagonals and barlows. Instead of a conventional locking thumbscrew that can push the eyepiece to one side, this innovative adapter uses a helical compression mechanism to not only grip the inserted eyepiece securely, but also center the eyepiece accurately within the adapter in the process. This mechanism is easily tightened or loosened by turning the large knurled twist lock ring at the top of the adapter.

The helical centering mechanism is controlled by an inner polypropylene compression ring (or collet) that will not mar your eyepieces. Its long length ensures that the adapter works well with smooth and recessed eyepiece barrels.

This practical and superb quality adapter is made from precision machined aluminum and is black anodized. The inside surface of this tube is black-matted to enhance contrast by reducing stray light reflections. It is also threaded to accept standard 2" telescope filters so you can use your 1.25" eyepieces with your 2" filters (be careful not to let the eyepiece barrel hit the filter though; To alleviate this problem, you can attach a 2" spacer ring (not included) to the Twist-Lock adapter to increase its overall length).

And that's not all. Unscrewing the twist lock ring completely exposes a male T-thread on the lower black barrel, which conveniently functions as a 2" prime focus (2"-to-T Thread) adapter by itself. So you're actually getting two adapters for the price of one! You'll want one for every scope!

Specifications (Complete adapter):

  • Total height = 1.20" (30.6mm)
  • Weight = 2.8oz (79g)
  • Compression band length = Approx. 16.5mm (0.65")
  • Maximum diameter = 2.2" (55.8mm)

Specifications (2" prime focuser part only):

  • Total height = 1.03" (26.1mm)
  • Optical length = 0.08" (2.15mm)
  • Clear aperture = 1.25" (31.7mm)
  • Weight = 2oz (57g)

Manufacturer part number: E-11

Reviews

4.7 (Based on 16 Reviews) 94% of reviewers recommended this product.
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    1. Guest

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      Review by Santiago I.
      1562123111
      Jul 2, 2019

      5.0 Good for the price

      Pros:

      Cons:

      Comments:

      It works for all my eyepieces, including the not-straight barrel of my ES 82°. It does a good job, especially for the price. No problem with adding a filter, but I have to take care the longer barrels don't hit it!

      It would be nice to have a better grip.

      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 Sir L.
      1559296879
      May 31, 2019

      5.0 A Must Have Accessory

      Pros:

      Cons:

      Comments:

      I've had my telescope for about 1.5 years. I've always ended up getting frustrated switching eyepieces because of things like it binding up because I wasn't going 100% straight in or a set screw was in 0.000001" too much. I knew there had to be a better way. Enter the Blue Fireball 2" to 1.25" Twist Lock Self Centering Eyepiece Adapter. A few quick turns and the eyepiece slips out with ease. A few quick turns and the eyepiece is securely locked into place. One of the best features is that you can open it extra wide so no more binding as you try to find that perfect angle. This should be on everyone's scope.

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

      This review was provided courtesy of AgenaAstro.com

    3. Buddy NY

      Buddy NY New Member

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      Review by Buddy
      1558042737
      May 16, 2019

      5.0 Great value

      Pros:

      Cons:

      Comments:

      I own the Baader reducer, I love it
      The Blue Fireball is its equal.
      It has some pros. Lighter, easy twist action..locks tight ..easy to loosen..made well.
      The only down side I can imagine is in winter wearing gloves. Might be hard to grip as it has a high polish finish.
      The Baader has the stem which might give better leverage with heavy gloves. But all that is trivial compared to the price difference
      This is a well made reducer and preformed as good as any others I've tried.. Good to go!!

      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 Bob S.
      1545395333
      Dec 21, 2018

      5.0 Awesome Reducer

      Pros:

      Cons:

      Comments:

      This is the second Fireball eyepiece reducer I've purchased from Agena Astro. It works well and the price point makes it a very good value.

      I have the more expensive BP reducer as well, but I find the Fireball easier to use.

      Highly recommended.

      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 Fred A.
      1533595724
      Aug 6, 2018

      5.0 A great product

      Pros:

      Cons:

      Comments:

      A well manufacture piece of equipment.
      Easy to use and holds the eyepiece securely.
      Best of all very fast shipping with Agena Astroproducts, a
      real pleasure doing business with them.
      Once again well made and easy to use.

      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 Michael B.
      1533045703
      Jul 31, 2018

      5.0 Blue Fireball/Twist lock self centering eyepiece

      Pros:

      Cons:

      Comments:

      Both are machined with high degree of precision. The finish gives them a very professional appearance. Best of all, my videocamera is held on axis very securely without any play or slop. The twist lock works much better than set screws to remove/reinsert EPs or the camera.

      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 Dalton H.
      1524023937
      Apr 17, 2018

      4.0 Well-Made Product

      Pros:

      Cons:

      Comments:

      Due to winter weather, I haven’t had a chance to try out this Blue Fireball EP adapter yet. However, I have checked how the product is made and how it works with my eyepieces and diagonal. The quality is excellent and the fit with my EPs and the diagonal is better than expected. I can’t wait for the weather to clear and give me a chance to put the Blue Fireball to work. The only reason I did not give 5 stars is because I have not yet used it for observing. I bet that 5th star is coming up.

      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 Eugene W.
      1517883250
      Feb 5, 2018

      5.0 Solved My Problem

      Pros:

      Cons:

      Comments:

      This solved my problem with sag using a barlow and ZWO cameras.
      This grabs and holds the barlow with camera firmly and keeps my optics on axis to give sharp images on the entire chip. Previously I had an Orion
      self centering adapter but some of these loosen too easily when the camera was re-oriented.

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

      This review was provided courtesy of AgenaAstro.com

    9. LevEye

      LevEye New Member

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      Review by Chris L.
      1516121785
      Jan 16, 2018

      5.0 Blue Fireball delivers again!

      Pros:

      Cons:

      Comments:

      This company delivers some of the highest quality machined parts I've ever purchased bar none. Don't hesitate to purchase a product made by them if your serious about the quality of your gear and you should be. Look up!

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

      This review was provided courtesy of AgenaAstro.com

    10. Guest

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      Review by Cordell
      1499638759
      Jul 9, 2017

      5.0 Fireball 2" to 1.25" Reducer Adapter Review

      Pros:

      Cons:

      Comments:

      Hi, This is my 3rd Fireball adapter as I have 3 scopes. These adapters are fantastic. Well made.
      I recently purchased a 2" diagonal. While using it I ended up with a different 2" to 1.25" adapter
      and I did not notice the thumb screw was hitting the lip or edge of the diagonal and chipping the finish.
      I was not pleased. The Fireball adapter has no set screws and it centers the eyepiece, so that fixed that,
      and now I don't have to worry about damaging my new diagonal.
      The Fireball adapter is a premium quality piece.
      I hope this review helps. Clear Skies!

      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 Patrick S.
      1482615072
      Dec 24, 2016

      5.0 Blue Fireball twist lock adapter

      Pros:

      Cons:

      Comments:

      Works great. Strong construction. Unscrewing the twist lock reveals T-42 threads so you actually get 2 adapters in 1.

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

      This review was provided courtesy of AgenaAstro.com

    12. Guest

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      Review by Skyviewer of San Bernardino.
      1476144000
      Oct 10, 2016

      5.0 Works well for 1-1/4 eyepieces, with "conditions"

      Pros:

      Strong Construction,Accurate

      Cons:

      Comments:

      This works well on a 2 inch focuser if you have many 1- 1/4 eyepieces and don't want to be fumbling around interchanging your 1 -1/4 adapter in the dark. I ordered a couple and keep them on my 1-1/4 eyepieces permanently. Make sure the intended eyepiece comes to focus at least 1/2 inch out from fully racked in as the adapter adds about 1/4 inch "out focus" due to the "grip ring" on it.

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

      This review was provided courtesy of AgenaAstro.com

    13. Guest

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      Review by Stargeezer of Modesto, CA.
      1444435200
      Oct 9, 2015

      4.0 Nice form and function

      Pros:

      Accurate,Easy to Use,Beautifully made,Strong Construction,Lightweight,Compact,Perfectly Finished

      Cons:

      Comments:

      I bought both the Antares and Blue Fireball twist lock 1.25"/2" adapters to compare... still using both after 3 months. The Antares has some sharp edges...not chamfered like the Blue Fireball. But the Antares has slightly different threads on the twist mechanism that grasp the eyepiece more quickly; the Blue fireball requires an extra twist. But the fit and finish of the Blue Fireball is much nicer than the Antares, e.g., edges are chamfered and filter threads are cleanly cut and it has a perfect anodized finish. The Antares filter threads are nearly unusable because they are so rough. I do like the twist lock form; it's clean, and centers the eyepiece nicely, maintaining a parallel position relative to the cone of light. If the Blue Fireball adapter locked eyepieces in more quickly, it would earn 5 stars from me.

      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 Stargeezer of Modesto, CA.
      1434585600
      Jun 17, 2015

      4.0 Comparison

      Pros:

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

      Cons:

      Requires An Extra Twist

      Comments:

      I bought the Blue Fireball (BF) and an Antares to compare. The BF is beautifully made with clean threads that work smoothly and chamfered edges that make it more finished. The Antares has squared edges (can hang up on the compression ring undercut when inserting in a diagonal) and the threading for filters was very rough. The Antares tightens the eyepiece more quickly because the chamfer used to compress the inner plastic ring has a steeper cut. The BF requires more turning of the ring to fully tighten the eyepiece (about 1.5 turns compared to 1/4 turn). The BF is made without labeling and is all black anodized which I like; the Antares has silk screened lettering on the knurled tightening ring. Both hold the eyepiece securely, the Antares just does it more quickly. I chamfered the bottom edge of the Antares adapter on a lathe and removed the lettering with acetone on a Q-tip. It looks and functions better. But the threading will never be as smooth as the BF.

      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 OCD Collimator of Brazil.
      1416268800
      Nov 17, 2014

      5.0 BlueFireBall. Universal hub for adapters

      Pros:

      Accurate,Easy to Use,Strong Construction,Lightweight

      Cons:

      Comments:

      BFB has every adapter you need to survive in the field.
      Since I'm obsessed with collimation, correct and repeatable centering of every part in the lightpath is essential. BFB solves it. Highly recommended!

      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 moonboy of Arlington, VA.
      1398297600
      Apr 23, 2014

      3.0 Cumbersome to use

      Pros:

      Accurate

      Cons:

      Difficult to Use

      Comments:

      The ring must be turned with 3 hand movements to release or tighten the eyepiece. Cumbersome and slow to switch eyepieces and more likely to knock the telescope off target.
      The adapter holds the eyepiece tightly and centered, as intended.

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

      This review was provided courtesy of AgenaAstro.com

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