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obsession 12.5 inch dob

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#1 larrytOMC200

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Posted 17 June 2013 - 06:21 PM

Hello all,
This is my first post on this forum. I have taken the plunge and am awaiting the delivery of an obsession 12.5 inch dobsonian with DSC. This will be the biggest scope I have ever had and it will be used for visual deep sky observing, and perhaps lunar/planetary observing, (I have an 8 inch F20 MCT from Orion Optics UK for this). I thought long and hard about this before purchasing as I know I could have got a cheaper dob with go to etc. However, I wanted a telescope that will last me for the rest of my life. I wanted a telescope that would be easy to use/move. I have tried using dobs before and the 'sticky' movements have always put me off. I made a 6 inch F11 dob many years ago which worked reasonably well and I suppose I felt a little bit nostalgic and wanted to get back to basics as it were with my hobby.
I guess I am airing out my worries that I have made the right decision. (I think I have), I did not want a larger scope as I wanted one that would be large enough to give pleasing views of DSO's, but not so large that I do not want to use it. (Our local Astronomical Society - Dunedin NZ)has a number of dobs. The 18 inch is a monster and difficult to track with. The 14 inch is much more usable for me (personal opinions here). The fact that obsession state 'buttery smooth' movement and non use of particle board for the telescope is what swung it for me. Anyway, delivery should be in mid July so I shall have to wait and see. I will keep you posted on how things pan out.
Regards and clear skies. Larry

#2 gaz-in

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Posted 17 June 2013 - 06:43 PM

Congrats....I think you have made and excellent decision. I have owned many sizes and think 12.5 is a great size. Big enuff to see deep but still not too tuff to carry and setup .

#3 okieav8r

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Posted 17 June 2013 - 06:58 PM

Larry, you'll love your new Obsession. They're very nice telescopes. I'm an Obsession owner myself, and I've been very happy with mine.

#4 Erik Bakker

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Posted 18 June 2013 - 02:19 AM

Larry,

Welcome on CN from the other side of the globe :)

You made a great decision with your 12.5 Obsession Classic.
Extremely enjoyable/practical scope.

Let us know how it works for you under those fascinating NZ southern skies!

#5 Achernar

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Posted 18 June 2013 - 09:28 AM

Under good skies, a 12.5-inch is more than enough for fantastic views of everything other than very remote galxy groups and clusters. It will be much lighter than a 15 or 16-inch of the same design. Moreover, with good optics, it will be a fanatstic performer on the planets, I see things on Jupiter and Saturn through my 15-inch I cannot through a small telescope.

Taras

#6 larrytOMC200

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Posted 19 June 2013 - 05:33 PM

Taras,
Thank you for your encouraging comments. You have correctly identified a couple of the reasons I went for the obsession 12.5 inch telescope. I wish you well. Larry

#7 ohioalfa64

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Posted 20 June 2013 - 09:26 AM

I agree with the above comments. My 12.5" Dob (f/4) is extremely portable, but just heavy and unstable enough to make me glad it isn't larger. Think about some extra counterweight for the bottom for low horizon viewing (up to 30* above horizon). Otherwise, the buttery-smooth movement, means you cannot hold an object in view, especially when you put a large heavy eyepiece in (Leica zoom with Barcon, or ES 30/82). By the time I look and position through the Telrad, then come around to the other side, the eyepiece weight as caused the scope to lower (again only on horizon viewing--such as PanStars Comet or last month's Jupiter). I'm thinking of putting a J-bolt through the bottom of the mirror box and hanging a free-weight there (5 lbs) on fishing line or Velcro or something.

#8 kfiscus

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Posted 20 June 2013 - 12:18 PM

To the OP, I have considered buying an Obsession (excellent reputation and build quality) and driving over to Wisconsin (next door) to pick it up and to save $$$ and worry during shipping. Driving from New Zealand would be a lot more trouble than it's worth.

I think you'll be glad of your decision.

#9 Mike B

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Posted 20 June 2013 - 12:40 PM

I'm thinking of putting a J-bolt through the bottom of the mirror box and hanging a free-weight there (5 lbs) on fishing line or Velcro or something.

You might consider a sliding-weight-on-rail system from ScopeStuff? I use a similar system on my Dob (Losmandy version, borrowed off my old CAT), and it enables a quick, smooth, easy, & infinitely variable method for achieving balance- no matter the viewing angle up/down, and/or the weight at the EP. I use anywhere from light EPs in a Paracorr up to beefy EP pairs in a BVer, and can dial in precisely what i need for balance, anywhere on the sky!

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#10 Paul Muller

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Posted 20 June 2013 - 01:31 PM

I have a 12.5 Astrosystem Telekit with OMI optics (the same optics that Obsession uses). It's amazing what you can see with it (the Orion Nebula looks amazing) and it's tough to go back to my 4" refractor after looking through the dob. I think you'll be very pleased by both the size and function of your telescope.

#11 ohioalfa64

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Posted 20 June 2013 - 02:09 PM

That sliding railed counterweight is fantastic. Where do I find it at Scope Stuff?

#12 Mike B

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Posted 20 June 2013 - 02:24 PM

Here's a Scopestuff link to get you started- there's actually quite a bit of stuff on his website, and you can always call him (Jim Henson) for advice; he's a very cool guy to deal with!
:grin:

#13 GeneT

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Posted 20 June 2013 - 10:47 PM

Your 12.5 incher doubles the light gathering of your 8. The Obsession Classic is a nice telescope. I think you made a great decision.

#14 MDB

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Posted 20 June 2013 - 11:09 PM

I really enjoy mine, it is small enough to transport easily and large enough to see deep. The 15 inch Obsession really tempted me but after using my 12.5 inch I am glad I didn't go bigger, the 15 would have been more than I would like to handle weight wise, I am 65 years old and want to be able to handle this scope for many more years. You made a great choice!

Mike

#15 larrytOMC200

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Posted 20 June 2013 - 11:53 PM

Thank you for all the replies, it has eased my mind somewhat as this is the most I have ever spent on a telescope. I feel I have the right balance between size and portability and ease of use. Keep well all. Larry

#16 larrytOMC200

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Posted 13 September 2013 - 05:54 AM

Hi all,
I have waited a while until I have had chance to use my dobsonian. I am pleased to say that it is dlivering views that I never thought I could get with a telescope that size. I have had the chance to go to a dark sky site and the amount of detail in the tarantula nebulea in the megallanic cloud was amazing, it looked almost 3D like (I was using a nebulea filter 'borrowed from an observing buddy"). Seeing structure in nebulea is a new experience for me and as for the star colours, well it has opened a new window for me with my hobby. As an aside, I am so glad I decided on the 12.5 inch size, as it is the max I would want to lug around and assemble. I enjoy being able to sit for most of my viewing. Other fellow amatures at my astro club (Dunedin Astronomical Society) have had nothing bad to say about the telescope or its optics, indeed I have heard comments such as "Ï want one of those for my next telescope".I am sorry I cannot quantify how the telescope performs, but just to say that I do not regret spending my money on it. (I am not knocking other suppliers either, it is just that the look and feel of the telescope is rught for me. Keep well all and clear skies. Larry

#17 GeneT

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Posted 14 September 2013 - 03:22 PM

For many, to include myself, a 12.5 incher is the perfect size. I have owned larger ones to include 18 and 20 inches. The increased size and weight led to a lot more hassle. My 12.5 inch Portaball is easy to load, transport, set up, take down, and store. After 55 years of observing, the 12.5 inch is where I ended up, and where I intend on staying.

#18 CHASLX200

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Posted 14 September 2013 - 03:33 PM

My 12.5" Obsession with a OMI mirror gave great views. On my best nites the planets looked great at 800x.

Chas

#19 Ed Wiley

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Posted 15 September 2013 - 12:43 PM

I love my 12.5 Obsession, perfect size for me in terms of handling a larger dob. Optical quality is excellent. If handles are no standard, make sure to add them on the order. Also encoders. I use a Sky Commander with mine but I know others like Argos Navigator.

Ed

#20 Photoner

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Posted 17 September 2013 - 01:04 PM

I really enjoy my Obsession 12.5 with encoders and the AN.

At 39 lbs the mirror box plus primary is only a pound heavier than some made-to-order 12.5 scope mirror boxes without the primary.

The scope balances very well with heavy, wide, 2" eyepieces and the curved spider is a nice feature. It provides very nice views of Saturn and Jupiter with good image scale, brightness, detail and color. Great eyepiece height for seated viewing.

DSO's are very satisfying with a 12.5". For example, I was surprised at how M37 was transformed going from 8" to 12.5".

To go significantly bigger would be extremely expensive,heavy, bulky and present major transportation and handling problems. The Obsession 12.5 mirror box fits in the backseat of a Corolla.

I've extensively studied other brands and sizes and decided that I did it right the first time with the choice of this scope for my situation and it has a very good price point.

Astro system topped off with this dob:
TV 102; Celestron C8HD; Obsession 12.5

#21 Deb and Todd

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Posted 17 September 2013 - 04:09 PM

I enjoy mine and often have comments on the views through my scope.

I haven't found the need to any counterwieght system.

+1 on getting the handles. Initially I did not, but then ordered up a pair several months later.

I too think this is about the right size. Know another individual with a 15" Obsession and he now wishes he would have got the 12.5".

You will enjoy your scope when you get it.

#22 swampdog

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Posted 18 September 2013 - 12:46 AM

Yes, enjoy the Obsession! This is also the one I'm saving for next...and the last!

#23 larrytOMC200

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Posted 21 July 2014 - 08:21 AM

Hi,
Just an update, I have finally figured out how to use my DSC's which came with the telescope. I have invested in the 3 skywatcher panorama eyepieces to go with the telescope and I just want you people to know that my enjoyment when looking through this telescope cannot realy be quantified. The large field of views make for superb vistas. Suffice to say that I laughed out loud on one occassion when viewing the megallanic clouds and our milky way, the views were so detailed and crisp. It has reivigorated my enjoyment at looking at our incerdible universe.
Anyway, if people think that 12.5 inches is not a 'big'telescope, and not able to deliver superb images of galaxies etc, please believe me when I say, one will not be dissapointed!
Thanks for reading. Keep well all. Larry

#24 GeneT

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Posted 21 July 2014 - 05:34 PM

A 12.5 inch Obsession is a nice sized telescope. I own a 12.5 inch Portaball, and the 12.5 inch is just the right size for me. Your 12.5 inch telescope will pull in twice the light of your 8 inch. Your 12.5 incher will be an excellent planetary and deep sky performer. For DSOs, get it out to a dark sky site for the best views.

#25 Starman1

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Posted 21 July 2014 - 06:31 PM

I moved up to a 12.5" about ten years ago. So far, I have no desire to go larger, even though I typically observe at a site in which there are many larger scopes.
A 12.5", for me, hits the magic size/transportability "eutectic" point.






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