Results 1 to 9 of 9
  1. #1
    Slip Mahoney's Avatar
    Slip Mahoney is offline White Dwarf
    Points: 547, Level: 10
    Level completed: 94%, Points required for next Level: 3
    Overall activity: 0%
    Achievements:
    365 Days+ Registered Achievement!2 Posts Achievement20 Posts Achievement!
    Join Date
    Nov 2011
    Location
    north carolina
    Posts
    9
    Points
    547
    Level
    10
    Thanks
    14
    Thanked 0x 0 Posts

    Default Barlow differences



    Well, its official. I purchased my first real telescope. A Skywatcher 8" retractable Dobsonian. Thanks to all that helped me understand. I do have a question after looking through all the stickies and whatnot.
    I am looking to buy a Celestron X-Cel LX Barlow lens. There are several
    different ones. Can anyone tell me what the difference is between the following seven sizes: 2.3 mm, 5 mm, 7 mm, 9 mm, 12 mm, 18 mm and 25 mm . What will the 2.3 do in comparison to the 25 mm and so on. Thanks for all the advice,
    Slip, The Last of The DeadendKids

  2. #2
    roverich's Avatar
    roverich is offline Moderator
    Points: 41,419, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    Got three Friends20+ Friends Achievement!First 1000 Experience Points5+ Referrals Achievement!100+ Threads Achievement!
    Join Date
    Jan 2009
    Location
    virginia .usa
    Posts
    7,913
    Points
    41,419
    Level
    100
    Thanks
    2,009
    Thanked 1,963x 1,528 Posts

    Default

    Congrats on your new scope ..It should keep you busy for years ..

    Those nembers you posted seem like eyepiece numbers ..Usualy barlow numbers are 1.5 , 2, 3, 4, 5 ... A 2 barlow will double your eyepiece ..If your scope has a focal length of 1000 and you use a 25mm you will have 40 power , With a 2x barlow it would be 80 ..
    16in Night sky Dobsonian F4.5 , 90mm refractor 500mm FL , 7in
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    classic Big-mac , Meade eye pieces with a few odd balls thrown in ...
    If you cant stand behind the american soldier ,
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Please stand in front of one ...

  3. The Following User Says Thank You to roverich For This Useful Post:

    Slip Mahoney (11-27-2011)

  4. #3
    Slip Mahoney's Avatar
    Slip Mahoney is offline White Dwarf
    Points: 547, Level: 10
    Level completed: 94%, Points required for next Level: 3
    Overall activity: 0%
    Achievements:
    365 Days+ Registered Achievement!2 Posts Achievement20 Posts Achievement!
    Join Date
    Nov 2011
    Location
    north carolina
    Posts
    9
    Points
    547
    Level
    10
    Thanks
    14
    Thanked 0x 0 Posts

    Default

    Thanks Roverich,
    Yes the numbers are as I see them where I will purchase them. But not knowing what the following means has gotten me twisted.
    It appears that I may be looking at two different lenses.
    One is this :
    CELESTRON NEW X-CEL 2x BARLOW LENS -1.25
    The other is this :

    The X-Cel LX series is offered in the following seven sizes: 2.3 mm, 5 mm, 7 mm, 9 mm, 12 mm, 18 mm and 25 mm.

    As I read, I think I got the Barlow mixed with some other Celestron lenses that come in different focal lengths .

    hence the 2.3 mm, 5 mm, 7 mm, 9 mm, 12 mm, 18 mm and 25 mm.
    Now if they too are barlow lenses then I have much to learn.

  5. #4
    roverich's Avatar
    roverich is offline Moderator
    Points: 41,419, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    Got three Friends20+ Friends Achievement!First 1000 Experience Points5+ Referrals Achievement!100+ Threads Achievement!
    Join Date
    Jan 2009
    Location
    virginia .usa
    Posts
    7,913
    Points
    41,419
    Level
    100
    Thanks
    2,009
    Thanked 1,963x 1,528 Posts

    Default

    It is a 2 power barlow in 1.25in size ..The other are focal lengths of there X-cel lx series of eyepieces .. Any brand will work with your scope , just have to watch out for real low numbers which will give your scope too much power ..Seeing conditions limit the use of real high powers on most nights ..

    What eyepieces do you have now ?
    16in Night sky Dobsonian F4.5 , 90mm refractor 500mm FL , 7in
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    classic Big-mac , Meade eye pieces with a few odd balls thrown in ...
    If you cant stand behind the american soldier ,
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Please stand in front of one ...

  6. The Following User Says Thank You to roverich For This Useful Post:

    Slip Mahoney (11-27-2011)

  7. #5
    Slip Mahoney's Avatar
    Slip Mahoney is offline White Dwarf
    Points: 547, Level: 10
    Level completed: 94%, Points required for next Level: 3
    Overall activity: 0%
    Achievements:
    365 Days+ Registered Achievement!2 Posts Achievement20 Posts Achievement!
    Join Date
    Nov 2011
    Location
    north carolina
    Posts
    9
    Points
    547
    Level
    10
    Thanks
    14
    Thanked 0x 0 Posts

    Default

    Just the lenses that came with the scope :

    2" Crayford Focuser insures ultra smooth focusing adjustments. , 4-element Plossl eyepieces (25mm & 10mm)

    So I was right that I was confusing others with a Barlow lens ?
    What will those others do ? I guess do you think they are necessary ?
    Thanks

  8. #6
    roverich's Avatar
    roverich is offline Moderator
    Points: 41,419, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    Got three Friends20+ Friends Achievement!First 1000 Experience Points5+ Referrals Achievement!100+ Threads Achievement!
    Join Date
    Jan 2009
    Location
    virginia .usa
    Posts
    7,913
    Points
    41,419
    Level
    100
    Thanks
    2,009
    Thanked 1,963x 1,528 Posts

    Default

    If you buy a 2x barlow you will have a 25mm and a 12.5 , a 10mm and a 5mm when using the ones you have with a 2x barlow ..I would buy something big like a 40mm or 36 or 32mm for low power viewing ..High powers are ok for the moon and planets but the views get dim with high powers ..And you can look for a 2in low power eyepiece since you have a 2in focuser...
    16in Night sky Dobsonian F4.5 , 90mm refractor 500mm FL , 7in
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    classic Big-mac , Meade eye pieces with a few odd balls thrown in ...
    If you cant stand behind the american soldier ,
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Please stand in front of one ...

  9. The Following User Says Thank You to roverich For This Useful Post:

    Slip Mahoney (11-27-2011)

  10. #7
    Slip Mahoney's Avatar
    Slip Mahoney is offline White Dwarf
    Points: 547, Level: 10
    Level completed: 94%, Points required for next Level: 3
    Overall activity: 0%
    Achievements:
    365 Days+ Registered Achievement!2 Posts Achievement20 Posts Achievement!
    Join Date
    Nov 2011
    Location
    north carolina
    Posts
    9
    Points
    547
    Level
    10
    Thanks
    14
    Thanked 0x 0 Posts

    Default Thanks Rover

    Thanks for your patience. I will get several and experiment with them all. I will let you know how it pans out. I appreciate your time !

  11. #8
    roverich's Avatar
    roverich is offline Moderator
    Points: 41,419, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    Got three Friends20+ Friends Achievement!First 1000 Experience Points5+ Referrals Achievement!100+ Threads Achievement!
    Join Date
    Jan 2009
    Location
    virginia .usa
    Posts
    7,913
    Points
    41,419
    Level
    100
    Thanks
    2,009
    Thanked 1,963x 1,528 Posts

    Default

    No problems but you dont need a bunch if you buy the barlow .. Use what you have then see what you need after a while ..Get used to your scope first ..Mabey buy a barlow and a lo power EP ..For now ..
    16in Night sky Dobsonian F4.5 , 90mm refractor 500mm FL , 7in
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    classic Big-mac , Meade eye pieces with a few odd balls thrown in ...
    If you cant stand behind the american soldier ,
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Please stand in front of one ...

  12. #9
    kencrowder's Avatar
    kencrowder is offline HYPER GIANT
    Points: 24,468, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    200+ Posts Achievement!400+ Posts AchievementFirst 1000 Experience PointsGhost Achievement! Averaging 5+ posts a day!50 Posts Achievement!
    Join Date
    Sep 2011
    Location
    Brea, CA
    Posts
    2,483
    Points
    24,468
    Level
    100
    Thanks
    3,833
    Thanked 3,285x 1,517 Posts

    Default

    Don't waste money on eps. I have several that I never use. When you have used your scope a while you will know what you want.

    The plossls have a limited aFOV and I've found the super plossls a nice cost effective feature. TeleVue makes very impressive eps, but they are large and expensive. Plossls also have a eye relief that is proportional to the fl, so short fl eps have very little eye relief. That's important to me since I wear glasses.

    There are too many factors other than fl to consider. It depends on what you want to do. That will become clear after you have used it a while.

 

 

Similar Threads

  1. Celestron Ultima 2x Barlow and Parks Gold Series Barlow
    By botoole in forum Telescope Accessories Forum
    Replies: 1
    Last Post: 07-25-2011, 12:55 PM
  2. Differences between GT, EQ, and SLT?
    By TambourineMan in forum Celestron NexStar Telescope Forum
    Replies: 7
    Last Post: 12-15-2008, 08:52 PM
  3. differences in dob 8's??
    By Davis in forum Amateur Astronomy Forum
    Replies: 1
    Last Post: 12-07-2004, 05:01 AM
  4. TAL Differences
    By James in forum UK Astronomy Forum
    Replies: 2
    Last Post: 10-09-2003, 01:08 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Powered by vBulletin® Version 4.2.0
Powered by vBulletin®
All times are GMT. The time now is 12:48 PM.