MMICKELS
Aluminum Knight
Reged: 01/20/04
Posts: 36050
Loc: Land of Shake and Bake
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I had a chance to view this weekend so of course I did. It was a dark spot, and I could see M13 naked eye. The seeing wasn't as good as I would have liked. My scope has a FL of 1911mm. I could see the irregular star shapes of the double double using a 20mm EP. With a 10mm EP there was black space between the stars. What mag is it typical for splitting this pair of doubles?
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Mark
I'm going outside to stand, so if anyone asks I am outstanding.
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 18806
Loc: Cumberland, R I , USA42N71.4W
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If skies were very good seeing (which they weren't) you would have been able to see the split with your 20mm eyepiece. I just posted the other day that I saw both e1 and e2 cleanly split with my AT1010 a 78mm scope with a 5mm UO ortho at a magnification of 96x. Normal magnifications are generally in the range of 125x to 150x. If the seeing is turbulent you may not even see it split at 150x.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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MMICKELS
Aluminum Knight
Reged: 01/20/04
Posts: 36050
Loc: Land of Shake and Bake
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Thanks Ed. 
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Mark
I'm going outside to stand, so if anyone asks I am outstanding.
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jmoore
Carpal Tunnel
Reged: 10/01/03
Posts: 1959
Loc: Beaufort, NC
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I split it last year at 62x, but couldn't do it at 48x. This was with a 5" Mak. Seeing was pretty good I think. Bill Grass has reported a magnification a tad lower than me, but I think the two of us have pretty good eyes for this sort of thing. Normal "split-mag" seems to be maybe 80x or above, based on other reports I can recollect.
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Hardin 12"
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MMICKELS
Aluminum Knight
Reged: 01/20/04
Posts: 36050
Loc: Land of Shake and Bake
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Maybe I should have also asked for a definition of a split. Is it when you can see black space in between the two stars?
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Mark
I'm going outside to stand, so if anyone asks I am outstanding.
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 18806
Loc: Cumberland, R I , USA42N71.4W
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That's the way I see it.
black space is split
Then there is
thin black line - that's split too
barely touching
barely overlapped
deeply notched
barely notched
elongated
barely noticed elongation.
these are all terms I use in my notes.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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MMICKELS
Aluminum Knight
Reged: 01/20/04
Posts: 36050
Loc: Land of Shake and Bake
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Thanks again Ed. I just wanted to make sure of what it is I'm looking for.
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Mark
I'm going outside to stand, so if anyone asks I am outstanding.
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brahtz
sage
Reged: 04/08/04
Posts: 203
Loc: Dragoer, Denmark
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I don't think that my eyes are anything special (far from), but recall that e1+2 split with black space at 66x with 80mm/f15 Zeiss lens. The seeing was moderate.
Henrik
Edited by brahtz (09/17/04 02:40 PM)
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F.Meiresonne
Post Laureate
Reged: 12/22/03
Posts: 4136
Loc: Eeklo,Belgium
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I can split e1+e2 from 120X on ,most of the time with moderate seeing in a 6 inch F/5 newt.Better is 150x and really stunning is 300X, a power i always rated much too high for the scope.Well, my 5mm ultrascopic with barlow lens does the trick,seeing permitting, which i find very, very surprising.
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Freddy
Obsession 18 inch #1638
Orion Optics 8 inch F/4.5 -1/8 wave optics -Vixen GP-E
22x85 Helios Apollo (=GO SS)
15x70 TS Marine (=Obie Ultra)
10x60 Helios Quantum 4(= Obie Mariner)
10x50 Fujinon FMT-SX
10x50,8x40 Helios Nature sport plus
Eyepieces in use :Pan 35,24,19, N13T6, Pentax 10, 7 XW, N9T6, TV2, BGO 12.5, 9 mm
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bierbelly
Postmaster
Reged: 01/23/04
Posts: 6179
Loc: Sterling, VA
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I split them Friday nite at 120x with my 4" refractor, but not at 75x.
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12" DSH
8" f/4 Vega MakNewt
6" MN66
TV85
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NewAstronomer
Post Laureate
Reged: 09/03/04
Posts: 3767
Loc: Northeast, PA U.S.A
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Question: What are e1 and e2? I'd like to try this out to determine capability of my equipment. Sounds like a good test. 
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NJScope
sage
Reged: 03/08/04
Posts: 332
Loc: NJ
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e1 and e2 (Epsilon Lyrae) are double stars ENE of Vega in the constellation Lyra which are easily split with binoculars. Each in turn can be split into the doubles 1A, 1B (2.8") and 2A,2B (2.3") with a telescope (theoretically ~2.4" aperture) but usually requiring a clear still night.
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Kevin
UnderOak Observatory
Celestron Hyperstar C8 SCT
Celestron Classic (1972) Orange C8 SCT
Vixen VC200L
Losmandy G-11 Gemini
Losmandy GM-8
Televue 76/SolarMax 40
Televue NP101
ST-402ME/Nikon D70 DSLR
SBIG DSS-7 Spectrograph
SBIG ST8-XME & CFW9 filter wheel
Starlight Xpress SXVF-8MC
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rcg
Pooh-Bah
Reged: 04/27/05
Posts: 1436
Loc: Saint Charles, Missouri
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Does it matter what type of eyepiece and the focal length for seeing the split. I have a televue 25mm plossl that will split it on steady seeing at 48x with my 8" achromat, usually at 66x with a 14mm radian and moderate seeing. but veiwing at different powers with different eyepieces I get varied quality of the image like some eyepieces are better than others, even in the same manufacturer "design" if the eyepieces have different focal lengths.
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Bob
8" f/6 achromat, homebuilt OTA
Alt/Az mount also home built
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Bob G.
8" F/6 Achromat home assembled on home made AltAz w/Pearl Nighthawk finder; currently parting out since return shipping fees for bad APM 8" Achro lenses are killing me  who would have thought you wouldn't get reimbursed for return shipping for optical junk? Live and learn!
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rcg
Pooh-Bah
Reged: 04/27/05
Posts: 1436
Loc: Saint Charles, Missouri
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Does it matter what type of eyepiece and the focal length for seeing the split. I have a televue 25mm plossl that will split it on steady seeing at 48x with my 8" achromat, usually at 66x with a 14mm radian and moderate seeing. but veiwing at different powers with different eyepieces I get varied quality of the image like some eyepieces are better than others, even in the same manufacturer "design" if the eyepieces have different focal lengths.
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Bob
8" f/6 achromat, homebuilt OTA
127mm Mak/Cass
Alt/Az mount also home built
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Bob G.
8" F/6 Achromat home assembled on home made AltAz w/Pearl Nighthawk finder; currently parting out since return shipping fees for bad APM 8" Achro lenses are killing me who would have thought you wouldn't get reimbursed for return shipping for optical junk? Live and learn!
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RRaubach
AstroCowboy
Reged: 01/26/05
Posts: 2173
Loc: Douglas (Converse County),WY
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To give a slightly more detailed finding direction: First find Vega ( a no-brainer!)and using a decent pair of binoculars. note that Vega is the brightest of an almost perfect equilateral triangle of stars. Another of these components will be an easy binocular double star = epsilon Lyrae. Under telescopic magnification of ~100X with decent skies, you MAY see it split into a "double double".
It is pretty atmosphere/seeing dependant, so don't give up--just keep after it night after night. A higher mag may be necessary at first, but once you have seen the split, it becomes easier to detect.
Rodger 
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Rodger
Meade SN-10 (UHTC) on Tak EM-200 mount/Antares rotating rings. Moonlite focuser.
Parallax 14.5" Newtonian on HD 200 mount (arriving soon!) w/ conical Royce mirror.
TMB 203 f/7 APO refractor on Tak NJP-160 mount.
Discovery 12.5" PDHQ
Schneider 18x80 "Flakfernrohr" binoculars/tripod mounted. Canon 15x50 IS binoculars
Unihedron Sky Quality Meter
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PJ Anway
Carpal Tunnel
Reged: 06/04/03
Posts: 2165
Loc: North Coast
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I experimented on a night of excellent seeing, and split e1 and e2 comfortably at 75X with my 80mm f/15 refractor. However, I find I prefer the view of them split at 120-150X.
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Clear Skies,
PJ
http://doublestarobserver.com
Refl.- 203/1420, Refr.- 100/1000, 75/500, 63/840, Bino.- 15X60, 10X50
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Bob Pasken
professor emeritus
Reged: 05/30/03
Posts: 512
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Used a Quantum-4 last night, I used e1 and e2 to test when the scope had cooled down enough. the Q-4 has a 60" focal length and I used a 25mm eyepiece and the builtin 1.5 barlow to give 90 power. I decided the scope was ready when I got back between the components.
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Starman1
Vendor (EyepiecesEtc.com)
Reged: 06/24/03
Posts: 17639
Loc: Los Angeles
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Quote:
That's the way I see it.
black space is split
Then there is
thin black line - that's split too
barely touching
barely overlapped
deeply notched
barely notched
elongated
barely noticed elongation.
these are all terms I use in my notes.
edz
In my 12.5" at 83X, I see both pairs split with Ed's second definition: "thin black line". At 58X, in good seeing, they appear "barely notched". Such are the advantages of a cooled larger aperture--smaller stellar discs and easier splitting.
As I calculate it, that makes the closer pair 190" separation at 83X, or 3' of separation. For a person with decent eyes, this is not exemplary. At 58X, the effective separation is 133", or just a little over 2', which I cannot resolve as double, easily
That explains why I can *just* see Epsilon Lyrae as double with my naked eye, but it is the limit of my vision. I guess I have 3' eyes (play on words in some European languages).
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Don Pensack
www.EyepiecesEtc.com
12.5" Teeter/Zambuto, 5" Maksutov
Sustaining Lifetime IDA member
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 18806
Loc: Cumberland, R I , USA42N71.4W
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bump
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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proud uncle
Carpal Tunnel
Reged: 01/22/07
Posts: 1688
Loc: Central Texas
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I split it last night with my 10" dob at 125x (Ed's thin black line). I did not try it at 100x (wished I would have)  But, 125x is the lowest power I've seen a split so far, and Eps Lyrae is still quite low. So, I am very pleased with that. Hopefully, when Lyra gets higher, I can get a 100x or lower power split.
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Kenneth
Nikon 10x50 binocular
Zhumell 10" Dobsonian (f/5)
eyepieces: 32mm (2" WA), 20mm, 12.5mm, 9mm (EWA), 6mm (TMB/BO Planetary), and 2X Barlow
Wratten filters: #21, 25A, 47, 56, 80A, and ND13
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