Results 1 to 6 of 6
  1. #1
    smokesha's Avatar
    smokesha is offline Main Sequence
    Points: 8,192, Level: 63
    Level completed: 14%, Points required for next Level: 258
    Overall activity: 0%
    Achievements:
    200+ Posts Achievement!First 1000 Experience Points365 Days+ Registered Achievement!750 Days+ Registered Achievement!2 Posts Achievement
    Join Date
    Sep 2009
    Location
    new york, usa
    Posts
    108
    Points
    8,192
    Level
    63
    Thanks
    15
    Thanked 39x 24 Posts

    Default Too much eye relief?



    I bought an eyepiece that has you position your eye pretty far away from the eyepiece in order to get a clear view. any closer and you get black cloudyness, sort of the opposite of vignetting. But my eye is so far away that I can see a ring of "light and stuff of my surroundings" outside the outer border of the eyepiece because I'm so far away. Is this normal? Is this why being in such a dark spot is important?
    Celestron Astromaster 130eq - 130mm f/5 Newtonian on an equatorial mount. Viewing from New York, USA

  2. #2
    GriffinBF's Avatar
    GriffinBF is offline Super Moderator
    Points: 37,400, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 7.0%
    Achievements:
    Got three Friends20+ Friends Achievement!First 1000 Experience Points5+ Referrals Achievement!100+ Threads Achievement!
    Join Date
    Feb 2009
    Location
    Alberta, Canada
    Posts
    6,717
    Points
    37,400
    Level
    100
    Thanks
    1,757
    Thanked 2,757x 1,841 Posts

    Default

    My EP's have fairly high eye relief at 20mm.. it's quite good though with the cups extended. What eyepiece did you buy?

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

  3. #3
    smokesha's Avatar
    smokesha is offline Main Sequence
    Points: 8,192, Level: 63
    Level completed: 14%, Points required for next Level: 258
    Overall activity: 0%
    Achievements:
    200+ Posts Achievement!First 1000 Experience Points365 Days+ Registered Achievement!750 Days+ Registered Achievement!2 Posts Achievement
    Join Date
    Sep 2009
    Location
    new york, usa
    Posts
    108
    Points
    8,192
    Level
    63
    Thanks
    15
    Thanked 39x 24 Posts

    Default

    it's a meade series 5000 26mm plossl. it has no cup extensions. At least that I know of, maybe they're hidden?

    I'm going to go check:

    Nope, definitely not
    Celestron Astromaster 130eq - 130mm f/5 Newtonian on an equatorial mount. Viewing from New York, USA

  4. #4
    WWPierre's Avatar
    WWPierre is offline HYPER GIANT
    Points: 64,445, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    10 Days registered3 Years + Achievement400+ Posts AchievementGhost Achievement! Averaging 5+ posts a day!1000 Days+ Registered Achievement!
    Join Date
    Jun 2009
    Location
    Squamish B.C.
    Posts
    6,948
    Points
    64,445
    Level
    100
    Thanks
    1,095
    Thanked 2,953x 1,808 Posts

    Default

    It's a wide angle, somewhere between 30 and 40mm, right? I have the same "problem" with my 35mm Siebert. It has to do with the size of the exit pupil, I think. I just make sire I have three point contact with Terra Firma so that I can hold my eye steady when I find the "sweet spot"

    Somebody did the math when I mentioned ordering this, and in theory, 35mm is past the capability of our scopes. I think the exit pupil is too big.
    Meade 16" LightBridge; Celestron G-8N Bird-Jones/motorized EQ5;
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    127 Mak/go-to EQ5; Burgess 127f8 refractor; Sky-Watcher 5" F/5 collapsible dob; 90mm Mak/motorized EQ2; Royal Astro 76/910-GEM; Meade 60x700 refractor/alt/az; Zhumell 25x100 Coin Ops; GalilleoScope. Celestron 8mm-24mm zoom; lots of fixed EPs,some good, some..not so much. A small collection of surveying instruments; a forest of tripods; Canon Rebel Xti. Confirmed gadget junkie; Custodian of the Magnetic North Pole (Send $1.00 to Pierre each time you use a compass.)
    49-41-37.03N 123-09-29.61W Calculated magnetic declination: 17° 39' East

    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.

    We have been broadcasting our presence to the Universe for 100 years now. If there is a detachment of Galactic Pest Control within 100 light years, they are already on the way.

  5. #5
    WWPierre's Avatar
    WWPierre is offline HYPER GIANT
    Points: 64,445, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    10 Days registered3 Years + Achievement400+ Posts AchievementGhost Achievement! Averaging 5+ posts a day!1000 Days+ Registered Achievement!
    Join Date
    Jun 2009
    Location
    Squamish B.C.
    Posts
    6,948
    Points
    64,445
    Level
    100
    Thanks
    1,095
    Thanked 2,953x 1,808 Posts

    Default

    Quote Originally Posted by smokesha View Post
    it's a meade series 5000 26mm plossl. it has no cup extensions. At least that I know of, maybe they're hidden?

    I'm going to go check:

    Nope, definitely not
    Well, that shoots my theory!
    Meade 16" LightBridge; Celestron G-8N Bird-Jones/motorized EQ5;
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    127 Mak/go-to EQ5; Burgess 127f8 refractor; Sky-Watcher 5" F/5 collapsible dob; 90mm Mak/motorized EQ2; Royal Astro 76/910-GEM; Meade 60x700 refractor/alt/az; Zhumell 25x100 Coin Ops; GalilleoScope. Celestron 8mm-24mm zoom; lots of fixed EPs,some good, some..not so much. A small collection of surveying instruments; a forest of tripods; Canon Rebel Xti. Confirmed gadget junkie; Custodian of the Magnetic North Pole (Send $1.00 to Pierre each time you use a compass.)
    49-41-37.03N 123-09-29.61W Calculated magnetic declination: 17° 39' East

    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.

    We have been broadcasting our presence to the Universe for 100 years now. If there is a detachment of Galactic Pest Control within 100 light years, they are already on the way.

  6. #6
    matthewota's Avatar
    matthewota is offline HYPER GIANT
    Points: 18,012, Level: 92
    Level completed: 78%, Points required for next Level: 88
    Overall activity: 2.0%
    Achievements:
    First 1000 Experience Points200+ Posts Achievement!365 Days+ Registered Achievement!750 Days+ Registered Achievement!100+ Threads Achievement!
    Join Date
    Jun 2009
    Location
    Riverside County, California USA
    Posts
    1,752
    Points
    18,012
    Level
    92
    Thanks
    23
    Thanked 964x 572 Posts
    Blog Entries
    1

    Default

    I bought a cheap 2 inch 50mm eyepiece at RTMC once. It had way too much eye relief, over one inch from the lip of the eyepiece housing when used on my F10 SCT. I gave it away to a kid in the astronomy club I was in that had an F5 dob, where it worked better.
    Matthew Ota
    10" Meade LX250GPS SCT, 80mm
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    ED80 Achromat, Lunt LS60THaPT H-alpha Solar
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

 

 

Similar Threads

  1. Long eye relief EPs
    By Sneakinoutatnight in forum Telescope Eyepieces Forum
    Replies: 7
    Last Post: 09-30-2010, 01:46 PM
  2. Eye relief
    By martinalennon in forum Telescope Eyepieces Forum
    Replies: 2
    Last Post: 11-17-2009, 04:06 AM
  3. 5mm EP with good eye relief?
    By Don Trinko in forum Telescope Eyepieces Forum
    Replies: 7
    Last Post: 06-01-2009, 09:22 PM
  4. plossles and eye relief
    By Cole Sachs in forum Amateur Astronomy Forum
    Replies: 2
    Last Post: 02-28-2008, 06:25 PM
  5. Is 8 mm eye relief a problem?
    By ROM SPACE KNIGHT NURSE in forum Amateur Astronomy Forum
    Replies: 3
    Last Post: 01-29-2005, 10:04 PM

Tags for this Thread

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 08:31 PM.