Just some history first. I own an 8 inch Dob Celestron starhopper - about 6 years old. I bought it to go deep sky playing. However changing circumstances put me in a situation where I can now only observe under urban skys - so faint fuzzies are a bit of a memory.

And just for the record I suck at star hopping. So I am a little over the need to spend so much time just trying to confirm I am even in the right part of the sky.

From what I can see goto technolgy is out of my price range at the moment, so something on a driven equatorial mount is the go.

I am planning to get involved with visual variable star observations and possibly double star measuring.


So my question is - How does an equivelent sized refractor say 120mm refractor stack up against an equivilent sized Maksutov. The refractor would only be achromatic, nothing like a Tak or Vixen.

Or do I throw my hands in the air and go up to a 12inch Dob?

The reason the Celestron has annoyed me so much, the whole thing is set up on the right hand side, and I have just never been able to get used to using the view finder with my left eye. The Dob I have seen is mounted on the left, with a right angled finderscope as a standard fitting.

I know this might sound confusing, but wondering if an easier to use scope such as the 12 inch would make the star hopping worth persisiting with

Finally, with the 12 inch, would it perform appreciably better under light polluted skies than the 8 inch?

Aperture always wins, so a 12 inch would perform better on deep space stuff than an 8 inch, even in light polluted skies.

Other things that help are shielding, both on the scope itself as well as in the vicinity to shield your eye from neighboring lights.

What kind of finderscope do you have? Would it be possible to rebuild your Dob in order to move the focuser or finders to the positions that are best for you? Maybe move the altitude bearings? Do you have both a 1x finder and a traditional finder? Do you have a good finder?

As to whether a refractor or a Mak would be better for you for splitting double stars and monitoring variable stars, hard to say. Personally, I would lean toward a refractor, but the long focal lengths also require a more solid mount and tripod.

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What kind of finderscope do you have?

9 x 50 Celestron straight through

Would it be possible to rebuild your Dob in order to move the focuser or finders to the positions that are best for you?

I asked about this at the local dealers (In Sydney Australia) I thought about exporting the optics into a new tube. I was told no one does this

Maybe move the altitude bearings?

It is the older style Hopper with the big dish like indented bearings. I have noticed the new models have done away with the idea. One huge drawback the design had - you needed to use a Celestron factory kit for encoders if you wanted to try goto.

Do you have both a 1x finder and a traditional finder? Do you have a good finder?

Yes I have a telrad. Reading through old posts on here, I noticed a few people talked about the problems you suffer when the object you are chasing is of the beaten track so to speak. Because I used to chase galaxies pretty hard, the majority are off the beaten track so to speak.

As an intrim measure I am thinking of getting a right angled finder and mount it on the Celestron to see how that goes with the comfort level. Even if it fails when I get the new scope (assuming the Dob) I can just remount it.

Thanks for the suggestions

A nice refractor would help you, with the increased contrast. Do not pay for GoTo technology. Get an oversized mount (per the scope package vendors) so you can add accessories, and a good big finderscope and a decent set of charts and you'll be set. This is not a hobby you jump into. You pay your dues, learn your way around the sky, and after a while, you realize that you are the Indiana Jones of astronomical objects. It's a gradual thing, and it's way more gratifying than saying "I have a computer attached to my telescope that points it at anyting I tell it to" - that's lame. You're not an astronomer at that point - you are a telescope owner and a somewhat observer. You might as well spend your time on the overpass "collecting" all 50 of the states' license plates.

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I agree with you turbo about learning the sky. I feel I have a pretty good working knowledge. It is when I go star hopping to some obscure corner of the sky for an 11th mag smeer, the frustration sets in

I cheated when I taught myself the constellations. I found a planet, say Jupiter, found out what constellation it was in. Then started joining the dots around it till I built a fairly good understanding of how it all went together.

To be fair, some of the fainter constellations are like guilt by association. I could not show you the outline of the particular stars, but I know the general area they are in.

Your suggestion about the mount was going to be my next question. Has anyone any experience with getting a Dob up on an equatorial mount while I think of it?

Actually, turbo-1, You have nailed the difference between amateur astronomers and (many) professional astronomers. A lot of the "pros" are like a big city apartment dweller who calls a cab, tells the driver the address of his destination, reads the paper until he is told "you're here" and gets out. He doesn't have a clue as to where "here" is.
Likewise, many professional astronomers tell the telescope operator the co-ordinates of the object, wait for the data to be collected and take the data when it is given to them. All without knowing where in the sky it actually is.

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Goto's have their place of importance. You can always not use the goto and just use the slew motors to find objects manually. However, that is usually observing by yourself or with some other experienced observers.

I like Goto's b/c I can set it on Saturn or Jupiter and everyone present (which I often observe around a small crowd of non-observers) can view the planet without you painstakenly re-aligning it for the next person. Newbies can't re-align your scope very well.

Goto's are also great when the moon is bright. Lock it on a planet and observe the moon orbits (Jupiter). During dark skies, put on your amateur astonomer hat and find objects manually.

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