Jump to content


Photo

Massive Telescopes...

  • Please log in to reply
37 replies to this topic

#1 Louietheflyisme

Louietheflyisme

    Viking 1

  • -----
  • Posts: 539
  • Joined: 17 Jun 2013
  • Loc: Australia

Posted 13 September 2013 - 10:00 PM

Hey Everyone,

Does anyone know the biggest of each types of telescope you can actually buy?

I'm pretty sure the Orion 50" Dob is the biggest Dob, and the Meade 20" is the biggest Cassegrain, but can anyone tell me any other telescopes that are bigger? Refractors, Dobs, Schmidt-Cassegrains?

Louis

#2 StarmanDan

StarmanDan

    Soyuz

  • *****
  • Posts: 3762
  • Joined: 27 Aug 2007
  • Loc: Deep in the heart of Texas

Posted 13 September 2013 - 10:44 PM

If money is not object, I'm sure you could find someone to build whatever size scope you want. Our club hired a contractor to build our observatory and 24" RC and they have made much larger instruments.

#3 Richard McC

Richard McC

    Vanguard

  • *****
  • Posts: 2391
  • Joined: 31 Dec 2004
  • Loc: Australia

Posted 13 September 2013 - 11:51 PM

How large is your wallet? Companies like DFM Engineering will build you as big a scope as you (or more likely an institution) can afford, e.g., DFM's "Standard Classical Cassegrain" offerings which include "50" - 1.3M CCT and larger" models. APM have shipped triplet refractors with apertures of at least 12" and the 3RF have a D&G (achromatic) refractor of 15" aperture.

#4 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 43916
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 14 September 2013 - 12:22 AM

I'm pretty sure the Orion 50" Dob is the biggest Dob,



I don't think you can actually buy any of those giant Orion Dobs. I don't think any of them have actually been made. I could be wrong..

Jon

#5 Louietheflyisme

Louietheflyisme

    Viking 1

  • -----
  • Posts: 539
  • Joined: 17 Jun 2013
  • Loc: Australia

Posted 14 September 2013 - 04:42 AM

I'm not actually interested in buying one, just looking for some info. Curious, I guess. I mean ones that aren't specially made for you as well.

#6 youngamateur42

youngamateur42

    Surveyor 1

  • *****
  • Posts: 1838
  • Joined: 21 Nov 2012
  • Loc: La Verne, CA

Posted 14 September 2013 - 08:42 AM

I'm pretty sure the Orion 50" Dob is the biggest Dob,



I don't think you can actually buy any of those giant Orion Dobs. I don't think any of them have actually been made. I could be wrong..

Jon


Theres a discussion regarding this and large scopes here:

http://www.cloudynig...5995921/page...

#7 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 43916
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 14 September 2013 - 09:02 AM

I'm not actually interested in buying one, just looking for some info. Curious, I guess. I mean ones that aren't specially made for you as well.


As others have pointed out, they were vaporware.. a webpage, a dream and nothing more.

One does not want to think about the largest Cassegrain you can actually buy.. it's just a question of how much you can afford.

APM on Astromart

If one needs a bigger scope than 80 inches, they are out there.

Jon

#8 Kfrank

Kfrank

    Surveyor 1

  • -----
  • Posts: 1804
  • Joined: 20 Dec 2008
  • Loc: Northern Colorado

Posted 14 September 2013 - 10:36 AM

How large is your wallet? Companies like DFM Engineering will build you as big a scope as you (or more likely an institution) can afford, e.g., DFM's "Standard Classical Cassegrain" offerings which include "50" - 1.3M CCT and larger" models. APM have shipped triplet refractors with apertures of at least 12" and the 3RF have a D&G (achromatic) refractor of 15" aperture.


I have talked with the owner of DFM engineering a couple of times and was fortunate to have him give us a tour of his operation. They do everything in-house from grinding the mirrors to fabricating the entire structure of these massive scopes. It's a fascinating operation. I'd love to own one of their 16 inchers but I'd have to sell my house to cover it. The 1.3 meter scopes are truly impressive.

#9 obin robinson

obin robinson

    Mercury-Atlas

  • *****
  • Posts: 2647
  • Joined: 25 Oct 2012
  • Loc: League City, TX

Posted 14 September 2013 - 04:38 PM

Okay here is stupid question time:

Instead of one huge 50" mirror why not just have four precisely aligned 20" telescopes like an inteferometer? Use a Mallincam or other high res camera for viewing. Link them together in a network. You would effectively have more aperture than one 50" telescope. Your complexity would be in synchronizing the telescopes together but with modern high resolution mounts it seems like it would be relatively easy. Has anyone done this before at home?

obin :question:

#10 Louietheflyisme

Louietheflyisme

    Viking 1

  • -----
  • Posts: 539
  • Joined: 17 Jun 2013
  • Loc: Australia

Posted 14 September 2013 - 05:03 PM

I know that's what they do with radio telescopes, so I don't see why you couldn't do it with a slightly higher spectrum, I guess...

#11 obin robinson

obin robinson

    Mercury-Atlas

  • *****
  • Posts: 2647
  • Joined: 25 Oct 2012
  • Loc: League City, TX

Posted 14 September 2013 - 05:09 PM

I know that's what they do with radio telescopes, so I don't see why you couldn't do it with a slightly higher spectrum, I guess...


Exactly. I mean technically two pairs of large binocular 20" telescope arrays would make for quite a bit of aperture.

obin :question:

#12 Louietheflyisme

Louietheflyisme

    Viking 1

  • -----
  • Posts: 539
  • Joined: 17 Jun 2013
  • Loc: Australia

Posted 14 September 2013 - 05:15 PM

Yeah... I wonder If you could make it so that instead of the light coming out of each eyepiece, it gets reflected somehow into a central scope or something...

#13 obin robinson

obin robinson

    Mercury-Atlas

  • *****
  • Posts: 2647
  • Joined: 25 Oct 2012
  • Loc: League City, TX

Posted 14 September 2013 - 05:53 PM

Yeah... I wonder If you could make it so that instead of the light coming out of each eyepiece, it gets reflected somehow into a central scope or something...


I was thinking it would only work with linked cameras. So for example let's say you had four Mallincams and could merge the image of all four of them together into one combined feed. It would be pretty cool if it worked.

obin :cool:

#14 Louietheflyisme

Louietheflyisme

    Viking 1

  • -----
  • Posts: 539
  • Joined: 17 Jun 2013
  • Loc: Australia

Posted 15 September 2013 - 04:32 AM

Yeah it would... Is that what they do with radio astronomy?

#15 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 43916
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 15 September 2013 - 05:27 AM

Yeah... I wonder If you could make it so that instead of the light coming out of each eyepiece, it gets reflected somehow into a central scope or something...


This is how large telescopes like the Keck's actually work. But the mirrors have to be aligned with the same precision as if the mirror were monolithic, that is a fraction of a wave length of light. This requires complex and expensive electro-mechanical systems that are computer controlled. It think it's not practical for anything but the largest telescopes.. and in this a game, a 50 inch is a small telescope.

Here is the history of the MMT, the original Multiple Mirror Telescope. The multiple mirrors have been replaced by a single large, (6.5 meter) mirror.

Jon

#16 Louietheflyisme

Louietheflyisme

    Viking 1

  • -----
  • Posts: 539
  • Joined: 17 Jun 2013
  • Loc: Australia

Posted 15 September 2013 - 05:40 AM

Yeah... Do you know what the biggest telescope anyone on these forums has made? Just out of curiosity...

#17 Ian Robinson

Ian Robinson

    Soyuz

  • -----
  • Posts: 3958
  • Joined: 29 Jan 2009
  • Loc: 33S , 151E

Posted 15 September 2013 - 05:42 AM

Maybe the 3 key questions should be
1) how much money do I have at my disposal (or my group's/club's disposal ?
2) what kind of telescope (specs, optical config) ?
3) how big a telescope can my observatory site make good use off (essentially how good is the seeing and how many clear windless nights) ?

I expect unless you are a multimillionaire, the only only options to get access to a mega amateur telescope is to build it completely yourself (except the mirror blank and aluminization of the finished optics) or to join a big rich club or to create a consortium of rich amateurs who are willing to pool money and resources and labor to create the beast and then use it on a time share type of arrangement.

PS I know someone who made a 48" ultralight using a very thin mirror.

#18 rnc39560

rnc39560

    Surveyor 1

  • *****
  • Posts: 1806
  • Joined: 23 Jul 2013
  • Loc: MS coast

Posted 15 September 2013 - 03:08 PM

The op doesn't WANT one made. Just wondering what the largest marketed scope in different categories are. Kinda curious myself now! :thinking: I do recall a thread with pics of a man, his father and brother unloading his scope. A forklift was used for the mirror and cell. It was 500 pounds (the mirror) crate included. I don't remember where, but will try to find it.

#19 Kfrank

Kfrank

    Surveyor 1

  • -----
  • Posts: 1804
  • Joined: 20 Dec 2008
  • Loc: Northern Colorado

Posted 15 September 2013 - 03:26 PM

The op doesn't WANT one made. Just wondering what the largest marketed scope in different categories are. Kinda curious myself now! :thinking: I do recall a thread with pics of a man, his father and brother unloading his scope. A forklift was used for the mirror and cell. It was 500 pounds (the mirror) crate included. I don't remember where, but will try to find it.


As a point of reference, the mirror in the DFM Engineering 1.3 meter scope weighs about 900 lbs.

#20 WarmWeatherGuy

WarmWeatherGuy

    Surveyor 1

  • *****
  • Posts: 1904
  • Joined: 27 Aug 2011
  • Loc: Orlando, FL 28° N, 81° W

Posted 15 September 2013 - 03:40 PM

Hey Everyone,

Does anyone know the biggest of each types of telescope you can actually buy?

I'm pretty sure the Orion 50" Dob is the biggest Dob, and the Meade 20" is the biggest Cassegrain, but can anyone tell me any other telescopes that are bigger? Refractors, Dobs, Schmidt-Cassegrains?

Louis


I found an ad in Sky & Telescope for these guys

http://planewave.com...age/telescopes/

They have a 27.6" for $200,000. It looks like a type of CAT.

#21 neotesla

neotesla

    Apollo

  • *****
  • Posts: 1121
  • Joined: 18 Nov 2010
  • Loc: Canada

Posted 15 September 2013 - 04:27 PM

JMI advertises these...

http://www.jimsmobil...m/buy_ntt40.htm

#22 sslcm56

sslcm56

    Vostok 1

  • -----
  • Posts: 189
  • Joined: 20 Jul 2012
  • Loc: Montgomery, Al.

Posted 16 September 2013 - 01:55 AM

Hey Everyone,

Does anyone know the biggest of each types of telescope you can actually buy?

I'm pretty sure the Orion 50" Dob is the biggest Dob, and the Meade 20" is the biggest Cassegrain, but can anyone tell me any other telescopes that are bigger? Refractors, Dobs, Schmidt-Cassegrains?

Louis


I found an ad in Sky & Telescope for these guys

http://planewave.com...age/telescopes/

They have a 27.6" for $200,000. It looks like a type of CAT.



I have spent a lot of time looking at the CDK700. Someday when I hit the lottery..... Last year they were only $180,000.00. I should have gotten it before the price increase. ;)

#23 Bill Weir

Bill Weir

    Mercury-Atlas

  • *****
  • Posts: 2534
  • Joined: 01 Jun 2004
  • Loc: Metchosin (Victoria), Canada

Posted 16 September 2013 - 11:48 PM

Yeah... Do you know what the biggest telescope anyone on these forums has made? Just out of curiosity...


http://www.nitesky.o...Telescopes.html

Some are members here and some aren't. Then there ia also Tom Clark who has built 36" and a 42" dobsonians. There is also Steve Aggas who built a 36". Then there is the Astronomical Research Institute where most of the scopes are built by the Head/owner operator where they go up to 50".
http://www.astro-res...y_directory.htm

These are all that I can think of off the top of my head.

Bill

#24 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 43916
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 17 September 2013 - 04:57 AM

Then there ia also Tom Clark who has built 36" and a 42" dobsonians.



Tom is a member of Cloudy Nights...

Jon

#25 Louietheflyisme

Louietheflyisme

    Viking 1

  • -----
  • Posts: 539
  • Joined: 17 Jun 2013
  • Loc: Australia

Posted 17 September 2013 - 06:20 AM

Has anyone seen any forum threads with these guys' telescopes shown on them? Just out of curiosity, again :).






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics