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Thread: In Need of Eye Relief

  1. #1
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    Default In Need of Eye Relief



    Orion SkyQuest XT6 Dobs
    (BST UWA 15mm & 25mm) (GSO 20mm & 9mm) (Celestron Omni 6mm & 15mm) (Orion shorty 2x Barlow
    ( *(Celestron X-Cel 12mm)

    I've recently started upgrading my EP's. My only complaint is that I can't see out of the 9mm & 6mm Plossl EP's. I've previously solved this problem with a 2x barllow, and a vow not to go below 12mm. However, I am noticing that the BST and X-Cel EP's have much better eye relief even down to the 9mm range.

    Are there any other advantages to using an (18mm X-Cel & Matching X-Cel 2x barllow) over just using a 9mm X-Cel?

    Thanks

    *New EP untested
    Orion Skyquest XT6 f8 / Orion 70mm f/10 EQ (Dobsonian & Refractor)
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    Default Re: In Need of Eye Relief

    For the EP lines with fixed (and long) eye relief, like X-Cel, BST and many other planetary EPs there is no advantage of using 18mm + 2x barlow vs 9mm EP. There is potential disadvantage that barlow can introduce some additional light scatter and loss of light.

    Thus, for faint targets like DSOs or difficult targets like tight doubles I try to keep amount of glass in the light path to the minimum and use dedicated EPs over EP+barlow.

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    Default Re: In Need of Eye Relief

    Bigzmey:
    That is sort of what I expected. I'll pick up a 9mm X-Cel LX, to round out my set. Thanks for the information.
    Clear Skys.
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    Orion Skyquest XT6 f8 / Orion 70mm f/10 EQ (Dobsonian & Refractor)
    EP's: 40mm, 25mm, 20mm, 18mm, 15mm, 10mm, 9mm, 6mm (X-Cel-LX, BST, Expl-Sci, & GSO)
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    Default Re: In Need of Eye Relief

    Quote Originally Posted by Sixfalls View Post
    Bigzmey:
    That is sort of what I expected. I'll pick up a 9mm X-Cel LX, to round out my set. Thanks for the information.
    Clear Skys.
    Can't go wrong with X-Cel LX line. They are good performers for the price and I prefer them over BST/TMB planetary and Dual ED lines.
    DeanD, Gabby76 and Sixfalls like this.

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    Default Re: In Need of Eye Relief

    Quote Originally Posted by Bigzmey View Post
    ................I prefer them over BST/TMB planetary.......
    Unfortunately, I prefer them over the BST as well. Sadly, I was happy, even thrilled with my BST, until I tried an X-Cel LX. Now I will not try anything else. Ignorance is bliss.......... When are Baaders going on sale?.. LOL

    No Seriously, I'm happy with my current EP's, but I will likely end up with another X-Cel LX or two.
    Orion Skyquest XT6 f8 / Orion 70mm f/10 EQ (Dobsonian & Refractor)
    EP's: 40mm, 25mm, 20mm, 18mm, 15mm, 10mm, 9mm, 6mm (X-Cel-LX, BST, Expl-Sci, & GSO)
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    Filters: 82A, 23A, #12, polarizer, neodymium
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  6. #6
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    Default Re: In Need of Eye Relief

    Quote Originally Posted by Sixfalls View Post
    Unfortunately, I prefer them over the BST as well. Sadly, I was happy, even thrilled with my BST, until I tried an X-Cel LX. Now I will not try anything else. Ignorance is bliss.......... When are Baaders going on sale?.. LOL

    No Seriously, I'm happy with my current EP's, but I will likely end up with another X-Cel LX or two.
    Story of my life. 5mm X-Cel LX was my first 'premium' EP after budget Plossls. After that I tried quite few EP lines over the years, keep what works for me and sell what does not to make room for more. I still have 5mm X-Cel LX though and acquired whole line. They are very comfortable EPs, perform well in all kind of scopes and for ~$50 used such a great value. Just stay away from 2.3mm, it is a lemon in otherwise nice line.
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