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I've been using binocular for more than a decade for visual observation. I'm thinking of upgrading to a telescope. The Dob caught my attention due to its simplicity in setup and also cost effectiveness. I was thinking of going for 8" or 10" Dob.

What I have also observed is - If I'm going to use dob, I need to keep moving the OTA frequently to keep the focus. If I'm going to use the dob alone, it is not an issue. But my concern is when I want to show the celestial objects to others, I need to frequently move the OTA to keep the objects in focus. It may become tiring if there are many people waiting to watch.

Has anyone encountered similar situation with dob? What are your thoughts? Did you ever feel that you should have gone for go-to mount instead of Dob? Any suggestions please?

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An 8 or 10 inch Newtonian telescope is principally a fine thing. Much telescope for little money.

A Dobson is a Newtonian telescope mounted on a rockerbox (see Alt/Az mount for a discussion). Consequences are: cheap, lightweight, trivial setup, your're either on your knees or on a chair, too seldom in between, it needs constant adjustment because the sky doesn't move that way.

If you want to track stars you need an equatorial mount, a cross of 2 axes of which one points to the celestial north (or south) pole. The same tube from the Dobson can also be mounted there. They can be motorized on one or both axes or/and have a computer built in to automagically find an object out of a database, then they are decorated with the "goto" attribute.

They are heavy, expensive (multiple times the price of a newton tube) and need a setup ritual each time they are moved. But once oriented, a motorized mount, connected to some software and computer, can be left alone for hours and will track the stars it points to.


So, the question is: do I want it light and cheap and don't I care about gymnastics, then the Dob. Do I want to go further and track things, do photography, than the other way. Perhaps with a sexy apochromatic refractor. But that's easily more than 20 times the price of a dob without camera stuff.

I personally don't do goto. Finding things is half of the fun for me. I go with equatorial mounts, a small portable one and one for photography setup I can drag outside. How about, you start with the Dob. If you bite, you're going to invest more anyway :-)

Edit: there is a third way (and potentially others) that might be worth considering, that would be a telescope like the one in this thread, a small reflector mounted on a computerized alt/az mount.

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    $\begingroup$ Re, "If you want to track stars you need an equatorial mount..." Here it is, six years later, and you can buy "go to" Dobsonian mounts, in which both axes of motion are motorized under computer control. Once the thing knows the time of day, where it is, and how it is oriented on the face of the Earth, it can automatically find and track any object in its sky catalog. $\endgroup$ – Solomon Slow Aug 19 at 17:15
  • $\begingroup$ @SolomonSlow Yeah that was a little provocative and general from my side. But tracking is not enough, the view must also rotate. An eq mount makes life so much easier. All people I know who do astrophotography (ok, they are not that many) use eq mounts. But you're right, with some effort you can do that with dobs, too, under sacrifice of the dob's simplicity, and it is not ideal. $\endgroup$ – user34599 Aug 19 at 17:26
  • $\begingroup$ Oops! I'm a newbie to this astronomy thing—just started shopping for a first telescope. I was thinking about photography, but on-the-cheap with my existing camera, and just for fun. I did not think about the image of an object rotating when an alt/az mounted tube tracks it... Thank you for the warning! $\endgroup$ – Solomon Slow Aug 19 at 18:07
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You are correct that a traditional dob will require frequent manual intervention to stop objects drifting out of view. There are 2 main to deal with this:

  1. keep to low magnification and use a wide angle eyepiece
  2. get a goto dob. These can be had for a reasonable price in many countries, particularly if you don't exceed 8" (200mm) aperture.

As @a_donda implies, you can see an awful lot with an 8" scope, especially if you have reasonably dark skies.

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Cost effectiveness? That also means you get what you pay for.

When you compare a Dob to a similar sized Goto telescope the Goto cost seems to be extremely high.

When you compare the versatility of the two, the dob is so far behind it thinks it is first.

That will upset a few dedicated Dob users but many of them have only used a Dob. They have accepted the limitations of the dob and are willing to live with them. I refuse to allow tradition to limit my viewing.

What is your maximum budget? Every penny that you can beg borrow or steal?

If all you can possibly afford is a dob then that's all there is to it. If you can afford a goto (new or used) that is your best choice and will give you the most enjoyment out of the hobby for years to come.

The traditional eyepiece has limitations as well. I suggest you take a look at what people can see with the electronic eyepieces. An electronic eyepieces is just a very sensitive camera that is generally used for direct viewing on a small screen rather than for making photographic images.

I have used Mallincams for nearly fifteen years and viewed with eyepieces for over fifty years before that.

There are a lot of objects in the deep sky one can see with the newest technology. When I used eyepieces my viewing was basically limited to the Messier and Caldwell lists. I recently compiled a new list of 26761 deep sky objects that can be seen with a 10" SCT setup like mine.

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  • $\begingroup$ Thank you all for your responses and perspective. Considering my objective of showing celestial objects to groups, tracking mount seems to be the option for me to go ahead. I'll do my research on available options, and based on my budget would go for one. $\endgroup$ – Suresh C Aug 9 at 10:16

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