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Thread: Barlow Lens Vs Telecentric Lens

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    Default Re: Barlow Lens Vs Telecentric Lens



    It is no coincidence that Explore Scientific makes a 4.7mm eyepiece in their two most popular lines... just a perfect match to the thousands of f/4.7 Dobs around the world.

    That said, a 4.7mm, 5mm, or barlowed 10mm is going to require a night of excellent seeing to attain a good focus. It's simply math. Now the moon is an exception to that. You can view the moon through a Coke bottle. If you want some fun, slap a 3mm Zhumell planetary EP in that Dob and look for cigarette butts on the moon.

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    Default Re: Barlow Lens Vs Telecentric Lens

    Quote Originally Posted by Lowjiber View Post
    Now the moon is an exception to that. You can view the moon through a Coke bottle.




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    Default Re: Barlow Lens Vs Telecentric Lens

    Quote Originally Posted by Lowjiber View Post
    It is no coincidence that Explore Scientific makes a 4.7mm eyepiece in their two most popular lines... just a perfect match to the thousands of f/4.7 Dobs around the world.
    I think I'm going to splash out and go with both an ES 6.7mm and an ES 2x Focal Extender. I have a 10mm, a 26mm and a 31mm and that should have me covered. The ES 4.7mm is tempting, but from what I can gather they tend to gather dust. One day perhaps…
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    Default Re: Barlow Lens Vs Telecentric Lens

    Quote Originally Posted by rogercorbett View Post
    I think I'm going to splash out and go with both an ES 6.7mm and an ES 2x Focal Extender. I have a 10mm, a 26mm and a 31mm and that should have me covered. The ES 4.7mm is tempting, but from what I can gather they tend to gather dust. One day perhaps…
    ES 6.7mm - great choice! If you are getting 2x extender or 2x barlow make sure it is 2". This way you can barlow your 26mm to 13mm and 31mm to 15.5mm. GSO 2" ED 2x barlow is a good budget alternative to the extender.

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    Default Re: Barlow Lens Vs Telecentric Lens

    By the way, how is Luminos 31mm working for you? I was always a fun of this series but feel intimidated by the weight and size of 31mm.

 

 
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