Results 1 to 6 of 6

Thread: Bad Eyepiece?

  1. #1
    snork's Avatar
    snork is offline Main Sequence
    Points: 2,009, Level: 28
    Level completed: 9%, Points required for next Level: 91
    Overall activity: 0%
    Achievements:
    5 Threads Achievement!50 Posts Achievement!2 Posts Achievement20 Posts Achievement!First 1000 Experience Points
    Join Date
    Dec 2011
    Location
    NE Ohio
    Posts
    94
    Points
    2,009
    Level
    28
    Thanks
    46
    Thanked 18x 14 Posts

    Default Bad Eyepiece?



    I recently purchased some used equipment and 1 item is a 2" 31mm Gto Proxima eyepiece. I tried using it last night and found I cannot get it to focus unless I pull it almost completely out of the focuser. I also have a Meade QX 30mm and it works just fine. Could the Proxima be bad or is it not made for use in my kind of scope(Orion XT8)?
    Orion XT8
    SkyWatcher 8" SCT
    Orion 100ED
    Criterion Dynascope 10
    Coulter Odyssey 13.1
    Scope Orbit 60mm

  2. #2
    Joe Lalumia's Avatar
    Joe Lalumia is offline HYPER GIANT
    Points: 61,001, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    200+ Posts Achievement!Ghost Achievement! Averaging 5+ posts a day!Got three FriendsFirst 1000 Experience Points20+ Friends Achievement!
    Join Date
    Jun 2010
    Location
    Quinlan, Texas
    Posts
    10,947
    Points
    61,001
    Level
    100
    Thanks
    6,772
    Thanked 5,156x 3,400 Posts
    Blog Entries
    1

    Default

    You probably have a REFLECTOR style telescope-- some eyepieces do not have enough focus range-- in your case an extension adapter for the focuser will permit you to come to focus with that eyepiece.

    Clear skies!
    ETX 125PE, Stellarvue 80mm BV & Televue TelePod tripod,
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    8" LNT, 10x50, 15x70mm binoculars, Stellarvue binoviewers, solar filters for all three
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    ..... plus a bunch of ham radios... Ham radio call sign - W1XWX

    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.


    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    TelescopeMan Web Site

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    search for W1XWX to see my amateur radio web site

    "If you can't explain it to a six year old, you don't understand it yourself.” - Albert Einstein

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

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

    snork (02-06-2012)

  4. #3
    KathyNS's Avatar
    KathyNS is online now Super Moderator
    Points: 172,469, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 84.0%
    Achievements:
    200+ Posts Achievement!Ghost Achievement! Averaging 5+ posts a day!First 1000 Experience Points400+ Posts AchievementGot three Friends
    Awards:
    Reply Award
    Join Date
    Nov 2010
    Location
    Nova Scotia
    Posts
    25,142
    Points
    172,469
    Level
    100
    Thanks
    6,658
    Thanked 14,975x 9,534 Posts
    Blog Entries
    3

    Default

    This is a pet peeve of mine - poor design. There is no reason at all why the eyepiece manufacturers couldn't get together and standardize the focal plane of all eyepieces. Make them all so that the focal plane is at the "shoulder" of the barrel. Then, all eyepieces would be parfocal. To have eyepieces that require extensions is ridiculous when all they need is a slightly longer barrel.

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.


    DSO AP:
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,LRGB filters; KWIQ/QHY5 guide
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    ; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome;
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    (pier);
    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.

  5. #4
    Devildadeo's Avatar
    Devildadeo is offline SUPER GIANT
    Points: 9,761, Level: 68
    Level completed: 37%, Points required for next Level: 189
    Overall activity: 0%
    Achievements:
    200+ Posts Achievement!First 1000 Experience Points50 Posts Achievement!5 Threads Achievement!400+ Posts Achievement
    Join Date
    Aug 2011
    Location
    Davenport IA
    Posts
    602
    Points
    9,761
    Level
    68
    Thanks
    270
    Thanked 224x 154 Posts

    Default

    Hey snork. I inadvertently moved my mirrors too close together at on time and had this issue. Check to be sure that your primary is set as far down in its cell as possible. Also make sure that you didn't move the secondary too far down to tube when last you collimated it. Adjusting these things worked for me.
    Vixen Foresta 7x50, Nikon Action 10x50
    ETX70-AT w/Reflex Finder
    XT8 (Tube Lined) w/9x50 RA illuminated and Rigel Quikfinder on TL Systems EQ Platform
    Explore Scientific 82 degree 30mm, 24mm, 18mm, 11mm
    Shorty
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    / Zhummel 2" Barlow
    Burgess Planetary 8mm and a handful of Plossls and Kellners

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

    snork (02-06-2012)

  7. #5
    Bob327's Avatar
    Bob327 is offline HYPER GIANT
    Points: 41,366, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    10 Days registered200+ Posts Achievement!First 1000 Experience PointsGot three Friends365 Days+ Registered Achievement!
    Join Date
    Sep 2009
    Location
    Frederick Maryland
    Posts
    9,247
    Points
    41,366
    Level
    100
    Thanks
    19
    Thanked 4,039x 3,068 Posts

    Default

    I have a 2" 31 mm Proxima eyepiece and it works very very well in my SCTS...not a heck of a lot of difference between it and my 35 mm Panoptic...

    I too am betting your are using a Newt that does not have enough back focus to allow you to focus the eyepiece...

    Bob G
    CPC1100 housed in a slotted domed observatory (Exploradome) 4 and 5 inch refractors for use from the lawn, a 8" Sct (NS 8i) for star parties...
    I Hate the winter so I use heated Motorcycle clothing to stay warm while observing in winter
    Retired, also have 2 other hobbies
    1. tinker with older Corvettes (6 in garage)
    2. make a heck of a lot of sawdust in my wood shop.

  8. #6
    snork's Avatar
    snork is offline Main Sequence
    Points: 2,009, Level: 28
    Level completed: 9%, Points required for next Level: 91
    Overall activity: 0%
    Achievements:
    5 Threads Achievement!50 Posts Achievement!2 Posts Achievement20 Posts Achievement!First 1000 Experience Points
    Join Date
    Dec 2011
    Location
    NE Ohio
    Posts
    94
    Points
    2,009
    Level
    28
    Thanks
    46
    Thanked 18x 14 Posts

    Default

    I am using an 8" Orion Dobsonian. Like I said the 2" Meade 30mm works fine but not the Proxima. Didn't realize there aren't standards used among manufacturers. That is good to know.
    Orion XT8
    SkyWatcher 8" SCT
    Orion 100ED
    Criterion Dynascope 10
    Coulter Odyssey 13.1
    Scope Orbit 60mm

 

 

Similar Threads

  1. 2nd eyepiece
    By Granpa_Cobra in forum Astronomy Beginners Forum
    Replies: 14
    Last Post: 12-19-2011, 04:43 PM
  2. eyepiece help for C8
    By ramkitty in forum Astronomy Beginners Forum
    Replies: 5
    Last Post: 07-27-2011, 03:51 AM
  3. Eyepiece or Eyepiece + Barlow?
    By kingmeow in forum Telescope Eyepieces Forum
    Replies: 7
    Last Post: 09-15-2010, 02:58 AM
  4. Best Eyepiece for CPC 800
    By markus7 in forum Celestron NexStar Telescope Forum
    Replies: 1
    Last Post: 07-31-2010, 01:48 PM
  5. decent cost eyepiece for eyepiece projection?
    By Jon Ives in forum Amateur Astronomy Forum
    Replies: 1
    Last Post: 09-07-2009, 07:44 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 07:12 PM.