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RussL
Music Maker
Reged: 03/18/08
Posts: 1925
Loc: Cayce, SC
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Hi, I am considering purchasing a 26mm Q70 for my 120ST. I know there are better eyepieces out there, and I suppose I might not get the best edge performance in such a fast scope, but the price is right. I can upgrade later. That's kind of a waste of money to go that route, but I don't wanna wait any longer to make use of my new AT dielectric quartz 2" diagonal. I suspect that if the performance falls off toward the edge I will still have a nice central view enough to make it a pleasing richfield experience. What ya'll think?
Also, would I like a 2" 2x barlow along with it? Thanks in advancefor any comments. 
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--Dawg, the Russell
"Akita mani yo." Observe everything as you walk. (--Lakota)
Celestron Celestar 8 Standard SCT, f10
Celestron 80mm Wide View ref., f5
Orion 120ST ref., f5
Criterion RV-6 Dynascope, Newt., f8, (c. 1962)
Sears Discoverer 60mm ref., f7, (c. 1973)
Celestron Ultima DX 10x50, 6.5 TFOV
Tasco 7x35 wide
Several mediocre eyepieces
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JayinUT
I'm not Sleepy
Reged: 09/19/08
Posts: 940
Loc: Utah
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I own a Q70 32mm that I use in a XT8 and a XT10 and there is a slight edge performance but the overall performance is excellent. Pleiades look really good in it.
Here are some reviews:
Positive Review Excelsis
Astromart Reviews
Cloudy Night Use Returned His
The link in that post doesn't work anymore FYI. Hope those help.
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Jay in Utah
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Location: Lat: 40.514N Long: -112.032W
Mortal as I am, I know that I am born for a day. But when I follow at my pleasure the serried multitude of the stars in their circular course, my feet no longer touch the earth.
— Ptolemy, c.150 AD
My Blog
Edited by JayinUT (11/07/09 11:29 AM)
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RussL
Music Maker
Reged: 03/18/08
Posts: 1925
Loc: Cayce, SC
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Thanks a bunch, Jay. The first two reviews are very encouraging, especially the guy who tried the Q70 26mm in his 120ST. I am particularly interested in richfield viewing, thus my purchase of the 120ST. I think the 70° AFOV will be nice, and enough for me. The outer edges will be there more for a spatial effect rather than looking at directly, so if there's any distortion I don't think it will bother me. Plus, I will be getting just over a 3° TFOV at 23x. Right now I am seeing a 2.1° TFOV using my modest 25mm Celestron SMA Wide (Kellner)--actually not a bad eyepiece that came with my Celestar 8 SCT. I get 24x with it in the 120ST. Plus it gives me a 5mm exit pupil which is big enough, and not too big. The longer focal length Q70s will give me too big an exit pupil for good contrast, although the lower powers would yield a larger TFOV. The 26mm is just right, and I believe I'll order it.
Thanks again for replying. Clear skies to you.
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--Dawg, the Russell
"Akita mani yo." Observe everything as you walk. (--Lakota)
Celestron Celestar 8 Standard SCT, f10
Celestron 80mm Wide View ref., f5
Orion 120ST ref., f5
Criterion RV-6 Dynascope, Newt., f8, (c. 1962)
Sears Discoverer 60mm ref., f7, (c. 1973)
Celestron Ultima DX 10x50, 6.5 TFOV
Tasco 7x35 wide
Several mediocre eyepieces
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russell23
sage
Reged: 05/31/09
Posts: 419
Loc: Upstate NY
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I used the Orion 38mm Q70 with a 120mm f/8.3 achromat. Edge performance was awful in the outer 25% of the field. The inner 75% was very sharp and had nice contrast. As I've said before, I would love to have a field stop to thread into the Q70's that would cut them down to a 60 degree field.
I did try the 32mm Garrett optics version of the Q70 line and it was pretty much the same - excellent sharpness and contrast in the center, but the outer 30% was bad.
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stevecoe
"Astronomical Tourist"
Reged: 04/24/04
Posts: 2635
Loc: Arizona, USA
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I have the 32mm version and am happy with what I got for the price I paid, as usual with Orion stuff. The central 75% is quite good in f/8 refractor.
Enjoy;
Steve Coe
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TeleVue 102 refractor on CGEM mount
10 inch f/4.7 Newtonian
Author "Deep Sky Observing" Springer-Verlag
Author "Nebulae and How to Observe Them" Springer
Canon Xt astrocamera with Hutech modification
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Feidb
super member
Reged: 10/09/09
Posts: 120
Loc: Nevada
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I use the whole set, 26mm, 32mm, and 38mm in my f/4.5 16" and yeah, the edge is bad, but all I care about is the sweet spot which is actually pretty good. I use the 26mm the most. You can't beat the price either, especially for a 2" Erfle variation. I'd go for it unless you are a "pinpoint to edge of the field" freak. Doesn't sound like you are so the 26mm should do just fine.
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Present gear:
16" Meade LightBridge
Meade 50mm straight through-finder
Lumicon green laser pointer
Orion Q-70 26mm, 32mm, and 38mm
Parks 2X 2" Barlow
1 1/4" X 2" Hyperion 17mm
1 1/4" X 2" Hyperion 8mm
1 1/4" 18mm Russell Optics Bertele
1 1/4" 12.5mm and 6mm Coulter Optical Orthoscopics
1 1/4" X 2" 32mm Edmund Scientific war surplus Erfle
Tirion star atlas (white stars, black background) hand-laminated
Megastar
And a partridge in a pear tree
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RussL
Music Maker
Reged: 03/18/08
Posts: 1925
Loc: Cayce, SC
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Well, I hope it's not quite that bad in my 120ST at the edge, but there's only one way for me to find out, I guess. Gosh, I'm restricted in so many ways: 1)-I wear glasses when I observe, so eye relief is important; 2)-I have a fast scope; 3)-funds are limited; 4)-I live in a red zone.
I bet you could make a field stop for your eyepiece, even if it's just paper, and fit it in the end. I don't know what it's like in the end, though. Is there room?
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--Dawg, the Russell
"Akita mani yo." Observe everything as you walk. (--Lakota)
Celestron Celestar 8 Standard SCT, f10
Celestron 80mm Wide View ref., f5
Orion 120ST ref., f5
Criterion RV-6 Dynascope, Newt., f8, (c. 1962)
Sears Discoverer 60mm ref., f7, (c. 1973)
Celestron Ultima DX 10x50, 6.5 TFOV
Tasco 7x35 wide
Several mediocre eyepieces
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