Results 1 to 5 of 5
Like Tree15Likes
  • 2 Post By Asterion
  • 4 Post By musiclucho
  • 6 Post By jaetea
  • 3 Post By KT4HX

Thread: Eyepiece Measurement.

  1. #1
    Asterion's Avatar
    Asterion is offline SUPER GIANT
    Points: 3,590, Level: 39
    Level completed: 60%, Points required for next Level: 60
    Overall activity: 0%
    Achievements:
    2 Posts Achievement5 Threads Achievement!20 Posts Achievement!50 Posts Achievement!200+ Posts Achievement!
    Join Date
    Dec 2015
    Location
    Minnesota
    Posts
    684
    Points
    3,590
    Level
    39
    Thanks
    193
    Thanked 110x 100 Posts

    Default Eyepiece Measurement.



    I have a question concerning how an eyepiece is measured. How is an eyepiece measurement determined? If I have a 30mm eyepiece what is measured to give me that 30mm? Is it a formula or the actual measurement of one of the lenses used in its construction?
    MCox and mightyboosh like this.

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


    Celestron AVX EdgeHD 8" SCT, Featertouch FTM-CPC8 Focuser, ADM Dual-VX Saddle with ADM Vixen dovetail bar, EdgeHD .7 Focal Reducer, Celestron StarSense Autoalign, WO DDG SCT Rotolock Focuser, Telrad Finder, ES 82deg 30mm-18mm-11mm-6.7mm eyepieces, Baader Hyperion Zoom Lens, Hyperion 2.25x Barlow Lens, Baader 2" SCT Visual Back w/Filter Holder, ASTF-200 Solar Filter, various filters, assorted accessories and a Nikon D7100.

  2. #2
    musiclucho's Avatar
    musiclucho is offline HYPER GIANT
    Points: 23,645, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    2 Posts Achievement365 Days+ Registered Achievement!20 Posts Achievement!5 Threads Achievement!750 Days+ Registered Achievement!
    Join Date
    Sep 2012
    Location
    Boulder Creek, CA
    Posts
    3,246
    Points
    23,645
    Level
    100
    Thanks
    713
    Thanked 1,095x 830 Posts

    Default Re: Eyepiece Measurement.

    30mm in that case, talks about the eyepiece focal lenght. The focal lenght is the distance between the beggining of the lens and the point it gets focused so you can see the image. (You can google it also because my english is not that good )
    DeanD, bladekeeper, MCox and 1 others like this.
    路易斯 LG
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    Skymaster 15x70, Up-close 10x50, SCT 6" on a CG4 EQ mount
    8x50 RACI and RDF. 9mm X-Cel LX, 15mm Luminos and 40mm Omni.
    My astro-adventures and sketches: http://pollutedskiesstargazing.blogspot.com/

    "A full appreciation of the universe cannot come without developing the skills to find things in the sky and understanding how the sky works." Alan Dyer

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

    Asterion (04-25-2016)

  4. #3
    jaetea's Avatar
    jaetea is offline Maven-like Entity
    Points: 159,636, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 8.0%
    Achievements:
    365 Days+ Registered Achievement!750 Days+ Registered Achievement!2 Posts AchievementFirst 1000 Experience Points20 Posts Achievement!
    Join Date
    Sep 2011
    Location
    Honolulu, HI
    Posts
    7,909
    Points
    159,636
    Level
    100
    Thanks
    1,224
    Thanked 3,100x 2,414 Posts
    Blog Entries
    17

    Default Re: Eyepiece Measurement.

    Hi,

    LG has given you what you asked but here is some additional (a lot of additional) information about the eyepiece and telescopes and how it all works. This page is from a very large work on telescope optics. I believe it is the definitive work on optics for the amateur astronomer.

    Here is the page: TELESCOPE EYEPIECE (select contents in upper right hand corner to get to the beginning of the document).

    Cheers,
    JT
    Main: C-stron CPC1100 #2
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    :
    8" f/7.5 Dob mounted Newt AP
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    :
    TPO 6" RC f/9 &
    ES 80mm f/6 APO G&G Scope: Meade 102mm f/7.8
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Guide Scopes: 70 & 80mm fracs Mounts: C-stron AVX CGEM & GT Alt-Az, Cameras: Canon T3i 2, ASI120MC Binos: 10X502,10.5X70,15X702, 25X100 EPs: ES: 21 100, 30 82 X-Cels: 9,12,18,25 Clubs: RCA & HAS

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

    I never met a scope I didn't want to keep.
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    "My God, it's full of stars."
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

  5. The Following 2 Users Say Thank You to jaetea For This Useful Post:

    Asterion (04-25-2016),rickg18704 (04-25-2016)

  6. #4
    KT4HX's Avatar
    KT4HX is offline HYPER GIANT
    Points: 102,795, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    365 Days+ Registered Achievement!First 1000 Experience Points750 Days+ Registered Achievement!1000 Days+ Registered Achievement!200+ Posts Achievement!
    Join Date
    Dec 2008
    Location
    Virginia
    Posts
    11,786
    Points
    102,795
    Level
    100
    Thanks
    1,443
    Thanked 8,098x 4,361 Posts
    Blog Entries
    200

    Default Re: Eyepiece Measurement.

    At the below link is some basic terminology you may run across when talking about eyepieces. Hope this helps clear up any questions you may still have about eyepieces in general.

    A Guide to Eyepieces
    Alan || My DSO Blog:
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    ---------------------------------------------------------------------------
    Astro Sky 17.5 f/4.5 Dob ||
    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.
    f/5 Dob || Zhumell Z10 f/4.9 Dob
    ES AR127 f/6.5 and ES ED80 f/6 on Twilight-II Mount
    ES 82 24mm, 18mm; Pentax XW 10mm, 7mm, 5mm
    ---------------------------------------------------------------------------
    Astronomers: We look into the past to see our future.

  7. The Following User Says Thank You to KT4HX For This Useful Post:

    Asterion (04-25-2016)

  8. #5
    Asterion's Avatar
    Asterion is offline SUPER GIANT
    Points: 3,590, Level: 39
    Level completed: 60%, Points required for next Level: 60
    Overall activity: 0%
    Achievements:
    2 Posts Achievement5 Threads Achievement!20 Posts Achievement!50 Posts Achievement!200+ Posts Achievement!
    Join Date
    Dec 2015
    Location
    Minnesota
    Posts
    684
    Points
    3,590
    Level
    39
    Thanks
    193
    Thanked 110x 100 Posts

    Default Re: Eyepiece Measurement.

    Thanks for the information everyone. It's exactly what I needed to know!

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


    Celestron AVX EdgeHD 8" SCT, Featertouch FTM-CPC8 Focuser, ADM Dual-VX Saddle with ADM Vixen dovetail bar, EdgeHD .7 Focal Reducer, Celestron StarSense Autoalign, WO DDG SCT Rotolock Focuser, Telrad Finder, ES 82deg 30mm-18mm-11mm-6.7mm eyepieces, Baader Hyperion Zoom Lens, Hyperion 2.25x Barlow Lens, Baader 2" SCT Visual Back w/Filter Holder, ASTF-200 Solar Filter, various filters, assorted accessories and a Nikon D7100.

 

 

Similar Threads

  1. Eyepiece size measurement
    By LarryG in forum UK Astronomy Forum
    Replies: 1
    Last Post: 08-15-2011, 11:38 PM
  2. Eyepiece size measurement
    By LarryG in forum General Astronomy Forum
    Replies: 0
    Last Post: 08-20-2003, 04:56 AM
  3. Eyepiece size measurement
    By Joe S. in forum General Astronomy Forum
    Replies: 0
    Last Post: 08-20-2003, 01:55 AM
  4. Eyepiece size measurement
    By psc@prairienetX.org in forum General Astronomy Forum
    Replies: 0
    Last Post: 08-19-2003, 06:29 PM
  5. Eyepiece size measurement
    By psc@prairienetX.org in forum UK Astronomy Forum
    Replies: 0
    Last Post: 08-19-2003, 06:29 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 02:50 AM.