WAVT
professor emeritus
   
Reged: 08/22/10
Loc: Bellingham, WA
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Re: Best EPs for a XT10i?
[Re: TahoeNoob]
#5538786 - 11/25/12 02:04 PM
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You have chosen a great scope! The 10" push-to Dob is a favorite for lots of folks. Good luck with it.
The 11mm ES 82° eyepiece is a great one, and priced well. It will blow the socks off the 10mm plossl that comes with those scopes. It also barlows very well. I like the the GSO 2X 1.25" barlow as you can unscrew the lens and make it a 1.5X barlow as well. The 11mm ES 82° and a barlow will really give you some very good moderately high power viewing options.
Depending on your budget, I would also recommend a low power wide field eyepiece. In a 1-1/4" size, you can't do any better than a 32mm Plossl (for the money) Sterling, GSO 32mm Plossls are decent. The TV 32mm Plossl is excellent.
Moving up and out to a 2" low power, wide field eyepiece will enable you to take in some wonderful large patches of sky and really put objects in context with their surroundings. The 10" dob has good wide field capabilities that you should take advantage of.
The TV 31mm Nagler coupled with a Paracorr is the gold standard for gorgeous wide field views in your scope, but... the cost is astronomical.
There is an aboration called coma that is inherant in your scope. Cheap low power eyepieces do a *BLEEP* job of correcting for it and you will see seagulls instead of stars, especially around the perifery of view. TV Naglers and some of the ES eyepieces do a better job correcting for coma, and the paracorr all but eliminates it. Most people are so stunned by the wide field views that they don't notice or object to the coma they see when looking thru a good quality low power eyepiece, and for them a paracorr is not a necessity.
The 30mm ES° eyepiece strikes a good balance between price and quality. For around $250 you will get huge enjoyment cruizing the milky way and it will take in Pleiades nicely.
I bought a 38mm Orion Q70 clone(an Agena 38mm SWA) and use it in my 10 dob and really like it. Of this inexpensive line of 70° eyepieces, the 38mm is the best of the lot. Yes, the exit pupil is wasteful, and the stars have tails in the outer 1/3 of view but I still keep going back to it every time I have my 10" dob out. I bought it used on CN classifieds for $60. I would suggest you keep yours eyes open for a similar deal. You just might get hooked on big wide fields and end up investing in premium optics. You will always be able to sell it if it doesn't float your boat.
Good luck with your new scope.
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JohnMurphyRN
sage
   
Reged: 09/09/12
Loc: Near St Louis
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Re: Best EPs for a XT10i?
[Re: WAVT]
#5538828 - 11/25/12 02:18 PM
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Depending on your budget, I would also recommend a low power wide field eyepiece.
Moving up and out to a 2" low power, wide field eyepiece will enable you to take in some wonderful large patches of sky and really put objects in context with their surroundings. The 10" dob has good wide field capabilities that you should take advantage of.
The TV 31mm Nagler coupled with a Paracorr is the gold standard for gorgeous wide field views in your scope, but...
The 30mm ES° eyepiece strikes a good balance between price and quality. For around $250 you will get huge enjoyment ...
I concur...
There's an ES 82* 30mm in the EP classifieds for $200 (not mine).
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TahoeNoob
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Reged: 10/31/12
Loc: Sierra Nevada
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Re: Best EPs for a XT10i?
[Re: JohnMurphyRN]
#5538852 - 11/25/12 02:31 PM
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I think I'm starting to get a handle on this. Tremendously useful information here!
Thank you everybody!
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Warren914
member
   
Reged: 03/21/12
Loc: Nova Scotia, Canada
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Re: Best EPs for a XT10i?
[Re: TahoeNoob]
#5538882 - 11/25/12 02:50 PM
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The Baader Hyperion 8-24mm zoom with 2x ED Barlow would give you a wide range of focal lengths down to 4mm, in either 1-1/4 or 2-inch format.
I use mine in 2-inch format with a GSO ED barlow. I find it is easier to turn the knob to find optimum magnification rather than fumble through multiple eyepieces.
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panhard
It's All Good
   
Reged: 01/20/08
Loc: Markham Ontario Canada
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Re: Best EPs for a XT10i?
[Re: Warren914]
#5538902 - 11/25/12 03:00 PM
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I use my 8mm & 13mm Hyperions the most. I must also mention that I also have the fine tuning rings.
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csrlice12
Postmaster
   
Reged: 05/22/12
Loc: Denver, CO
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Re: Best EPs for a XT10i?
[Re: TahoeNoob]
#5538960 - 11/25/12 03:25 PM
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Because with the Orion, You'll spend as much time collimating your laser so that you can collimate your scope. Most lasers are that you breathe near them, they'll lose collimation. The glatter is factory tested by beating them on hard surfaces before they go out the door (true story). They don't lose collimation unless you drop them while skydiving.... Kind of like the difference between a Porshe and a Yugo......both are cars, but the Porshe is a fine tuned automobile.
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panhard
It's All Good
   
Reged: 01/20/08
Loc: Markham Ontario Canada
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Re: Best EPs for a XT10i?
[Re: csrlice12]
#5539039 - 11/25/12 04:19 PM
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Glatter is good. Not at all like the cheap ones.
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TahoeNoob
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Reged: 10/31/12
Loc: Sierra Nevada
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Re: Best EPs for a XT10i?
[Re: panhard]
#5539068 - 11/25/12 04:36 PM
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I doubt doubt that, but I can't even figure out what needs to be bought for a complete setup. Oh, and expensive!
If I go this route, it'll have to be in a 1.25" model... and it can't cost 265 dollars.
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csrlice12
Postmaster
   
Reged: 05/22/12
Loc: Denver, CO
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Re: Best EPs for a XT10i?
[Re: TahoeNoob]
#5539094 - 11/25/12 04:45 PM
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That's why I also earlier recommended the Cheshire/collimation eyepiece, which will give very good collimation results for visual use. Most people use these very, very effectively and have used them for years...and they are a LOT cheaper then the laser systems.
Edited by csrlice12 (11/25/12 04:48 PM)
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TahoeNoob
sage
Reged: 10/31/12
Loc: Sierra Nevada
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Re: Best EPs for a XT10i?
[Re: TahoeNoob]
#5539109 - 11/25/12 04:51 PM
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... also, from what I understand, you're centering a shadow that bounces back from the primary mirror, not the actual laser light that bounces back. As a result, they say it doesn't matter if the collimator "wobbles" a little bit in the focusing tube.
I saw a YouTube video where Howie even demonstrates this. Starting at about 9:10: http://www.youtube.com/watch?v=sd3stObWI_I
If that's the case, does it really matter what type of collimator you use?
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TahoeNoob
sage
Reged: 10/31/12
Loc: Sierra Nevada
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Re: Best EPs for a XT10i?
[Re: csrlice12]
#5539111 - 11/25/12 05:00 PM
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Thank you csrlise12! I meant to say "I don't doubt that" in the post above... not that I do doubt it. I'm certainly not doubting your expertise. You clearly know way more than I do and probably ever will! 
Even so, I think I'm going to go with an Orion Deluxe Collimator. I can't justify spending that kind of money on a collimator. Maybe later, when I find out that my system doesn't work, I'll see things differently.
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City Kid
Carpal Tunnel
   
Reged: 05/06/09
Loc: Northern Indiana
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Re: Best EPs for a XT10i?
[Re: TahoeNoob]
#5539112 - 11/25/12 05:02 PM
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... also, from what I understand, you're centering a shadow that bounces back from the primary mirror, not the actual laser light that bounces back. As a result, they say it doesn't matter if the collimator "wobbles" a little bit in the focusing tube.
I saw a YouTube video where Howie even demonstrates this. Starting at about 9:10: http://www.youtube.com/watch?v=sd3stObWI_I
If that's the case, does it really matter what type of collimator you use?
Yes it matters. When you are using the TuBlug and centering the shadow of the center spot you are adjusting the tilt of the primary mirror. However, you don't use the TuBlug when adjusting the tilt of the secondary mirror. In that case you are centering the laser to the center dot on the primary. If the laser itself isn't collimated then the tilt of the secondary mirror won't be correct.
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TahoeNoob
sage
Reged: 10/31/12
Loc: Sierra Nevada
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Re: Best EPs for a XT10i?
[Re: City Kid]
#5539119 - 11/25/12 05:11 PM
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That makes sense to me.
It's different parts of the whole process. I think I'm focusing too much on just one step of the process.
I need to take a break and think this over... is this a concept that all noobs struggle with?
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City Kid
Carpal Tunnel
   
Reged: 05/06/09
Loc: Northern Indiana
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Re: Best EPs for a XT10i?
[Re: TahoeNoob]
#5539140 - 11/25/12 05:35 PM
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I agree with csrlice12 that you can get by with a cheshire eyepiece for now. It would be a lot cheaper than the Glatter tools. What I wouldn't do is buy a cheap laser collimator. You can be more accurate with a cheshire than a miscollimated laser. Eventually you will see the need for better tools and you can spend the money then. Until then, learn to collimate with the cheshire. I would also suggest that you take a look at the Catseye collimation tools. They are every bit the quality of the Glatter tools. I have both the Catseye and the Glatter and I like them both. In fact the cheshire that Catseye sells would be great if it's not out of your budget.
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Tim D
super member
Reged: 10/08/10
Loc: Temecula, CA
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Re: Best EPs for a XT10i?
[Re: City Kid]
#5539200 - 11/25/12 06:25 PM
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You can use a Orion laser collimator and get the exact results as a TuBlug, I do it all the time, all you need is a barlow. See link http://www.smartavtweaks.com/RVBL.html Tim
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Billytk
sage
Reged: 04/22/12
Loc: Orlando, Fl.
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Re: Best EPs for a XT10i?
[Re: Tim D]
#5539454 - 11/25/12 09:36 PM
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You can use a Orion laser collimator and get the exact results as a TuBlug, I do it all the time, all you need is a barlow. See link http://www.smartavtweaks.com/RVBL.html Tim
Thank you! I finally understand! I can't wait to try this. Thank you!!!
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CosmoSat
scholastic sledgehammer
Reged: 07/24/09
Loc: India
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Re: Best EPs for a XT10i?
[Re: TahoeNoob]
#5539635 - 11/25/12 11:34 PM
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Even so, I think I'm going to go with an Orion Deluxe Collimator. I can't justify spending that kind of money on a collimator. Maybe later, when I find out that my system doesn't work, I'll see things differently.
Here are a few collimators to choose from..Collimation & Focusing Tools. Over the Orion collimator..I would rather suggest u the Agena 1.25" Side View Newtonian Laser Collimator with 2" Adapter which I believe is manufactured by GSO or this one...GSO 1.25" Newtonian Deluxe Laser Collimator III.
The 25mm plossl u hve giving a 5mm exit pupil and around 50x magnification shud take care of the low power views for now..u can consider one later if u are not happy with the views or if u find urself using those low powers most of the time.
Rather try finding an eyepiece of around 15mm fl for dso's.
For planetary I would suggest u the ES 4.7mm Eyepiece giving an 1mm exit pupil and about 250x magnification. with the 1.25" barlow..u would get 375x and 500x mag.
Clear Skies!
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TexasRed
scholastic sledgehammer
Reged: 05/17/11
Loc: East Texas
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Re: Best EPs for a XT10i?
[Re: CosmoSat]
#5539761 - 11/26/12 02:41 AM
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I bought an Orion Deluxe Laser Collimator and ended up giving it away with the warning that it was only useful as a cat toy. If I touched it while it was in the focuser, the red dot jiggled all over the place. If I turned it in a circle in the focuser, the red dot made a circle on the primary.
I replaced it with a much cheaper Cheshire/sighttube combo that works just fine, doesn't need adustment and has no moving parts to break or wear out.
Maybe if the scope were f/4 or less, and cost a fortune, I could see the need for laser precise collimation to squeeze out every ounce of possible performance. For a 10" f/4.7, just center the crosshairs in a cheap Cheshire and be done with it.
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csrlice12
Postmaster
   
Reged: 05/22/12
Loc: Denver, CO
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Re: Best EPs for a XT10i?
[Re: TexasRed]
#5539977 - 11/26/12 09:24 AM
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TexasRed is right. For now, use the Cheshire/sighttube combo. More accurate collimation would only really be needed for AP.
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howard929
Member
   
Reged: 01/02/11
Loc: Low End of High Ground
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Re: Best EPs for a XT10i?
[Re: csrlice12]
#5539997 - 11/26/12 09:46 AM
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TexasRed is right. For now, use the Cheshire/sighttube combo. More accurate collimation would only really be needed for AP.
As you know, a mis-collimated secondary results in a loss of light while a mis-collimated primary results in a loss of clarity. I found that getting collimation as close to spot on as I can before ventureing out is an important step for successful viewing. Couple that with changing collimation during a long viewing session due to tube flexure , it's handy to be able to collimate in the dark and IME that's where a barlowed laser set-up for tweaking the primary mirror really pays off.
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