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Best EPs for a XT10i?

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#26 csrlice12

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Posted 25 November 2012 - 03:25 PM

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.

#27 panhard

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Posted 25 November 2012 - 04:19 PM

Glatter is good. Not at all like the cheap ones. :grin:

#28 TahoeNoob

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Posted 25 November 2012 - 04:36 PM

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. :)

#29 csrlice12

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Posted 25 November 2012 - 04:45 PM

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.

#30 TahoeNoob

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Posted 25 November 2012 - 04:51 PM

... 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.c...h?v=sd3stObWI_I

If that's the case, does it really matter what type of collimator you use?

:shrug: :shrug: :shrug:

#31 TahoeNoob

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Posted 25 November 2012 - 05:00 PM

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.

#32 City Kid

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Posted 25 November 2012 - 05:02 PM

... 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.c...h?v=sd3stObWI_I

If that's the case, does it really matter what type of collimator you use?

:shrug: :shrug: :shrug:


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.

#33 TahoeNoob

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Posted 25 November 2012 - 05:11 PM

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?

#34 City Kid

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Posted 25 November 2012 - 05:35 PM

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.

#35 Tim D

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Posted 25 November 2012 - 06:25 PM

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

#36 Billytk

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Posted 25 November 2012 - 09:36 PM

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!!!

#37 CosmoSat

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Posted 25 November 2012 - 11:34 PM

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!

#38 TexasRed

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Posted 26 November 2012 - 02:41 AM

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.

#39 csrlice12

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Posted 26 November 2012 - 09:24 AM

TexasRed is right. For now, use the Cheshire/sighttube combo. More accurate collimation would only really be needed for AP.

#40 howard929

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Posted 26 November 2012 - 09:46 AM

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.

#41 TahoeNoob

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Posted 26 November 2012 - 11:43 AM

I don't mean to start a fist fight, but are the HoTech collimators (they're available on eBay) worthwhile?

BTW, there's also a 2" Glatter collimator available on eBay for a Buy It Now price of 220. (If those things were half the price, I'd probably bite the bullet and buy one.)

#42 csrlice12

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Posted 26 November 2012 - 11:53 AM

The Glatters are nice to have, but like anything, your budget is going to come into play. It took me many years before I started earning the money to allow me to afford some of the better equipment. You can get along fine with the manual barlow/laser method or the Cheshire collimation equipment for a much lower price. The difference for viewing will be negligible....

#43 JohnMurphyRN

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Posted 26 November 2012 - 12:43 PM

I don't mean to start a fist fight, but are the HoTech collimators (they're available on eBay) worthwhile?


I have one and like it. There's a used one in CNC reasonably priced (not mine).

I was using a cat-toy mounted with set screws in a piece of PVC for collimation before I got the hotech. With the use of a barlow, my primary was spot-on using that cobbled together makeshift(you don't center the return laser; you center the centerdot's shadow)....

#44 Dave Mitsky

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Posted 26 November 2012 - 01:52 PM

In case they haven't been mentioned already, the Baader Planetarium Hyperions are very good buys. The Celestron X-Cel LX eyepieces are quite good for planetary work.

The Explore Scientific 68 and 82 degree eyepieces are well worth considering, as has already been mentioned.

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#45 csrlice12

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Posted 26 November 2012 - 01:59 PM

I know we have been discussing eyepieces and collimater, etc...but let's not lose sight that the best thing you can do for your scope is to get it to dark skies. A collimated scope in dark skies will perform better with ANY eyepiece....

#46 howard929

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Posted 26 November 2012 - 03:03 PM

I don't mean to start a fist fight, but are the HoTech collimators (they're available on eBay) worthwhile?

BTW, there's also a 2" Glatter collimator available on eBay for a Buy It Now price of 220. (If those things were half the price, I'd probably bite the bullet and buy one.)


The rub with a laser like that one (GSO, Orion, Hotech) is they don't fit snugly in the focuser and don't set themselves in the focuser the same way with each insertion. That's not a problem for adjusting the primary mirror if a barlow is used but it's a disaster for adjusting the secondary mirror. I use a sight tube for that which is a once in a blue moon adjustment and a barlowed laser for the primary which I tweak quite often. So, yes, that HoTech should be fine for the all important primary mirror adjustments as long as you use a barlow with it.

#47 JohnMurphyRN

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Posted 26 November 2012 - 03:38 PM

I don't mean to start a fist fight, but are the HoTech collimators (they're available on eBay) worthwhile?

BTW, there's also a 2" Glatter collimator available on eBay for a Buy It Now price of 220. (If those things were half the price, I'd probably bite the bullet and buy one.)


The rub with a laser like that one (GSO, Orion, Hotech) is they don't fit snugly in the focuser and don't set themselves in the focuser the same way with each insertion. That's not a problem for adjusting the primary mirror if a barlow is used but it's a disaster for adjusting the secondary mirror.


I considered that, so after collimation was complete I removed and reinserted the hotech and it still showed centered. It's a tight fit in the focuser and returns to same orientation. FWIW, lately I just collimate with the hotech without barlow and call it done.

#48 TahoeNoob

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Posted 26 November 2012 - 04:58 PM

Is a "sight tube" the same as a Cheshire? I think I'll be getting one of those with my scope. It'll do, for now, until I have a better idea what I need/want.

#49 Dave Mitsky

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Posted 26 November 2012 - 07:38 PM

No, although a sight tube and a Cheshire "eyepiece" can be combined in one unit.

http://www.garyseronik.com/?q=node/165

http://www.tomhole.c...lowed Laser.htm

http://www.amateuras.../collimate.html

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#50 TahoeNoob

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Posted 27 November 2012 - 04:26 PM

Thank you. I bought one of those sight tube/Cheshire combo units last night.

Meanwhile, is a 3X barlow a bad idea? (I know they make them up to 5X, but are they worthwhile?)






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