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Thread: What to expect from a 2x barlow lense.

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    Default What to expect from a 2x barlow lense.



    I recently acquired an Orion 130st EQ with a 25mm lens. I ordered a no name 2x barlow to use in it. I understand that it should double the magnification, but this one does nothing to increase the magnification. What could I be missing?

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    Default Re: What to expect from a 2x barlow lense.

    It should do something noticeable, what were you trying to view?
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    Default Re: What to expect from a 2x barlow lense.

    Unless the Barlow is, for some odd reason, missing a lens inside the tube, it should provide twice the magnification of a given eyepiece.

    If the Barlow is missing its lens, i.e. it's just an empty tube, then there will obviously be no increased magnification; you would not be able to focus your scope at all.

    If the Barlow has its lens and does provide 2x magnification, but the lens is of very poor quality, e.g. a cheap plastic lens, it might degrade the view so much that you don't notice the increase in magnification.

    Are you using the Barlow correctly? The Barlow goes into the focuser and the eyepiece goes into the Barlow. Your 25mm EP then becomes in effect a 12.5mm EP. If you are trying to look through the Barlow by itself, that's the problem.

    Finally, if the object you are looking at is a star, it isn't going to look 2x bigger. Stars will always appear as point sources of light even at very high magnification.

    Hope this has helped!
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    Default Re: What to expect from a 2x barlow lense.

    If you are looking to a star with a barlow , bear in mind that you wont see any further magnification, bcuz the stars are too far and even if you put 1000x magnification , it will look the same with a shorter FOV only. Try the barlow on the moon to see if it has effect.

 

 

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