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gethen
2002-Nov-11, 05:01 PM
Looking for a little advice from the experienced telecope users out there. I have decided to invest in a real telescope and, other than cost, I have two major concerns. First, what about collimation of a reflector? Difficult? Time consuming? I've read that the Mak-Cas, because of the closed tube design, seldom needs collimation. Is this true? It appears that I would make a major concession to aperture to purchase a Mak-Cas in the same price range as a reflector. Would it be worth it?
Second, sorry guys, but size does matter. The prospect of wrestling a 35 pound (almost a third of my own weight) tube onto a tripod is daunting indeed, but if the smaller, lighter Mak-Cas would yield noticeably poorer views, I'll start pumping iron now.
Any advice is appreciated./phpBB/images/smiles/icon_confused.gif

<font size=-1>[ This Message was edited by: gethen on 2002-11-11 12:03 ]</font>

aurorae
2002-Nov-11, 05:23 PM
Here's a few links to try, there's lots more on the web. Good stuff:

http://www.prairieastronomyclub.org/buyers.htm

http://observers.org/TAC.cgi/Links/#EQUIPMENT

Find a local astronomy club. Go to a meeting, ask questions. Amateur astronomers tend to be a friendly lot.

If you are in the US, try
http://www.astroleague.org/al/general/society.html

or the Sky and Telescope web site.

Also, see if you can find a copy of the book Starware by Herrington. The 3rd edition has recently come out. It is a very good resource for the sort of questions you have asked.

<font size=-1>[ This Message was edited by: aurorae on 2002-11-11 12:25 ]</font>

Russ
2002-Nov-12, 12:29 AM
I'll attempt to give you some direct answers to your questions. I agree with Aurorae. Go to your nearest astronomy club/society and attend at least 5 star gazes. You don't say where you are from so I can't make any suggestions. Try here: http://dir.yahoo.com/Science/Astronomy/Organizations/Clubs/
or here: http://dir.yahoo.com/Science/Astronomy/Organizations/
to find a club.

[quote]
On 2002-11-11 12:01, gethen wrote:
Looking for a little advice from the experienced telecope users out there. I have decided to invest in a real telescope and, other than cost, I have two major concerns. First, what about collimation of a reflector? Difficult? Not really. Time consuming? A little but not hatefully so. I've read that the Mak-Cas, because of the closed tube design, seldom needs collimation. Is this true? Yes. On M-C's the secondary is "painted on" the primary lens, so it's not prone to being knocked out of collimation. It appears that I would make a major concession to aperture to purchase a Mak-Cas in the same price range as a reflector. Would it be worth it? This is subjective to a certain extent and why you want to attend some star gazes. You want to see if this matters to YOU. As you do your research, you'll hear one thing repeated ALOT. "AIE" or Aperture is everything. What they leave off is "Until you have to pay for it."
Second, sorry guys, but size does matter. The prospect of wrestling a 35 pound (almost a third of my own weight) tube onto a tripod is daunting indeed, but if the smaller, lighter Mak-Cas would yield noticeably poorer views, I'll start pumping iron now.
Any advice is appreciated./phpBB/images/smiles/icon_confused.gif 110 lbs. Whooooeeeee! You are a tiny dancer! You are less than half my own weight and about the same as my scope. /phpBB/images/smiles/icon_biggrin.gif My advice...start pumping!

As mentioned above Aperture is everything, until you have to pay for it. My personal experience: At my club there are two guys with "Big Iron", the kikd of scopes that take your breath away.

Guy one has a beautiful 6", fully apochromatic, refractor. All optics are fully computer figured and coated. It's the best money can buy, I'm guessing between $10-15K! It gives beautiful images of everything, planets, nebulae, younameit.

Guy two has a hand made dobsonian. It looks like it's made from plywood he stold off an old barn and a scrap aluminum ladder. It has a 36" hand figured primary. You have to stand on a fairly tall ladder to use it. He claims he's got $850 in it, $700 in the mirrors. It blows the refractor away. When you look at Saturn, you feel like you're standing on the rings.

The point of all of this is that you're going to have to decide what matters to you. eg. These guys wouldn't swap scopes for any money. This is why you have to go to the star gazes and look through as many scope types as you can get away with. Also, there may be people there trying to sell their scope and it may be one you like. A good time to wheel and deal.

A final note: The best scope for you is the one you'll use the most, regardless of it's other characteristics.

I hope this helped. /phpBB/images/smiles/icon_biggrin.gif

David Hall
2002-Nov-12, 12:50 AM
As long as you are just doing eye-only observing, a Dobsonian mount is all you need (although an equatorial mount is very convenient). You can save your money and put it into aperture.

But as soon as you want to do astrophotography, your costs skyrocket. You need scope, EQ mount with smooth tracking, camera equipment, and nowadays computer equipment to run it all.

And yes, don't forget the manhandling problem. A scope that's difficult to use will not get used often.

Cassegrains and the related types are good compromises. They are smaller and lighter, so they don't need big mounts and can be dragged out at just about any time. You can even get nice carrying cases that aren't much worse than small suitcases. But you will have to pay for the convenience.

Personally, my dream scope has always been the Parks combo newtonian/cassegrain. Two scopes in one. Whee! But ouch, the price. /phpBB/images/smiles/icon_frown.gif

http://scopecity.com/hit.htm

Russ
2002-Nov-12, 01:16 AM
Personally, my dream scope has always been the Parks combo newtonian/cassegrain. Two scopes in one. Whee! But ouch, the price. /phpBB/images/smiles/icon_frown.gif

http://scopecity.com/hit.htm


Personally my dream scope is the Keck installation. If you're going to dream, dream big! /phpBB/images/smiles/icon_biggrin.gif

Gsquare
2002-Nov-13, 01:44 AM
On 2002-11-11 20:16, Russ wrote:

Personally my dream scope is the Keck installation...


Yep, I'll go for that ....especially since Keck's added the awesome 'adaptive optics' system. I gotta get me one of those! 22 microarcsec. resolution!
Just put it on my credit card.

G^2 /phpBB/images/smiles/icon_biggrin.gif



<font size=-1>[ This Message was edited by: Gsquare on 2002-11-12 21:05 ]</font>

gethen
2002-Nov-13, 03:09 AM
Thanks to all for the info.
p.s. Although I really like the idea of the Keck, the shipping would probably kill me.