Purchase of my first Dobsonian

[NightSkyLK]

Hi All,

I’m new here and wanted to get some advice on my purchase of a Dobsonian in Australia.
This would be my second telescope and my first being a 3.5” catadioptric I used a decade back and haven’t since owned a telescope due to other commitments.

My thoughts are to buy a Dob since I’ve looked through some (8” 10” and 12”) and love the views. The 12” is what I wanted but I hear its always good to buy the size below so planning on buying a 10”. Also the 12” might be too big to handle. This is going to be used in the backyard and prefer the non-bulky size so again planning on a collapsible Dob rather than the full body.

I’ve gone through lots of reviews in here and other places and wanted to get opinions on the latest models of Dobs. Some of the articles and recommendations are old and I know they have improved on the bases and movements, focuser of the Dob so was wondering if anybody can recommend a particular model.

I’m looking at the following:
SW 10”(f/4.8) collapsible DOB - $1k with shipping included (Astro anarchy)
SW 8” (f/6) collapsible DOB - $800 with shipping(Astro anarchy)
SW 8”(f/6) collapsible GO-TO DOB - $1.6k with shipping(Astro anarchy)
GSO 10”(f/5) full body DOB - $1.1K with shipping(Andrews comm)

The GSO comes with 4 eye pieces(inclusive of a 2” 30mm SV GSO which is something I want to buy anyways) and a dual speed crayford and the SW with 2 eye pieces (10mm and 25mm)

Assuming budget is OK what would be the recommendation.
Also
1.Is the 8” GO TO a better option than the 10” SW non GO-TO version. Haven’t used a GO-TO before and I don’t know how complicated that would be?
2.Is the GSO 10” of better quality vs the SW 10”?
3.The SW 10” is f/4.8 so a faster scope. How much more of a pain is the collimation, aberration with EPs? I don’t have super quality EPs as yet and will be a future purchase?

My preference is the SW 10”(f/4.8) but happy to hear otherwise. Apologies for the long post and multiple questions but would love the insight of more knowledgeable people in here.

Thanks
Dineth

[m11]

Hi Dineth,

Congrats on your pending purchase.

If I had to choose it would be the 10inch sw collapsible dob. Good light gathering and portability for what you getting.

It will serve you well for many years.

M11

[notoriousnick]

Hi Dineth,


I've had a 10" collapsible SW since 2009 and have had no problem with it. The mirror is still in very good shape (but then, I store it inside). The SuperPlossls that come with it are pretty good, too.



If you want help with finding stuff in the sky, you can always turn the 'scope into a 'Push-to' system later on by installing say, a Nexus II system. I have one on order.


I'm sure you'll have fun though, whatever you decide to get!

Edit: 1. SW is pretty good
2. IMHO, GOTO is more stuff to go wrong, can be noisy. A push to system can be cheaper and faster to use (like the Nexus II) - you can use your phone or laptop to track where your telescope is pointing. The phone/laptap then shows you where to push your telescope to find something - with pretty good accuracy by all accounts. But then, I'm biased :).
3. I've had no problem with F4.7 when using the eyepieces that I have, nor with collimating the 'scope.

Cheers,
Nicholas

[raymo]

I had the SW 10" collapsible for years. The tubes are robust, so you only have to do a very occasional collimation, not each time you extend it. If you have
any interest in doing basic imaging, make sure that the scope you buy can
be used for that purpose. Some Newtonians[Dobs, for our purposes] don't have enough back focus to allow for attaching of a camera. All SW Newts do.
Both parts of the 10" are easy to carry, but the 12" is a bit more of a beast,
unless you are youngish and sturdy.
raymo

[NightSkyLK]

Oh good to know. Also ill look into the Nexus II I didnt know about that.
Yeah my concern was the accuracy of collimation and happy to hear that its not an issue.
Thanks for information Nicholas

[NightSkyLK]

Yeah that was my thoughts as well with the 12" being a bit more bigger in size. I have plans of AP at some point but might end up having a separate setup for that if i get the budget approved :D:D
Thanks for the info!

[NightSkyLK]

Good to hear i'll stick with the SW 10" then. Thanks!

[Outcast]

+1 for encoder/Nexus equipped Dob...

I first encountered the Astro Devices encoders & Nexus DSC when they were included in the purchase of a custom built 12" 'travel friendly' dobsonian. The scope is a Gondwana Marana made by our own Mental4Astro (Alex)...

When I purchased the scope, the thought of only having push to & no tracking was of some concern to me but, nevertheless, I pressed ahead...

Since owning one, I have to say the not having tracking is a non-issue. I love my encoders & nexus dsc so much, I have in fact changed my other visual setups & now have a Stellarvue M2C mount coupled with Astro Devices encoders, mounted atop a Berlebach Uni 18 tripod. I use my existing Nexus DSC with this combination.

It is pure joy to use... minutes to setup, very simple align process & I'm off galavanting through the skies, nailing every target I set... the countdown numbers in Alt/Az are so simple to follow it's ridiculous.

I have yet to use the wifi capability on my Nexus DSC to hook it up to Skysafari but, I daresay, that will work extremely well too...

Chat to Serge at Astro Devices, he is very easy to deal with & a great source of advice. He makes an encoder kit to suit a range of Dobsonians, including Skywatcher & they are well priced IMHO. The install instructions he provides with his kits are extremely easy to follow &, if you get stuck, he is more than happy for you to call & he will guide you along.

You will need to discuss with him which Nexus best suits your needs & it's availability..

Definitely worth having for visual use & quite honestly, far simpler to use than any of the goto systems I have used previously = much more pleasurable visual astronomy experience.

Cheers

[raymo]

Hi Carlton, I don't know what the encoder system costs, but unless it is cheaper than I imagine it to be, he might be as well or better off going for
the GoTo version in the first place.
raymo

[Outcast]

Looking online at prices:

Push to Collapsible 10" SW = $1200
Goto Collapsible 10" SW = $2000

Encoder kit for SW Dob = $160 US
Nexus II = $$200 US

Even at Serge's listed prices there is a significant cost saving & you may be able to get a 'package deal'. Obviously, one would have to talk to Serge to determine if he can/is prepared to do a better deal as a bundle perhaps...

Cheers

[Max Vondel]

I have had the GSO 12" Dob and am currently using a modified 10" GSO Dob.
Both are great optically.
Don't be swayed by poor quality EP's from Andrews (budget constraints allowing).
GOTO all seems nice till you have to stuff around in the dark making it work.
As others have said there are cheaper add-ons.
If I were in your shoes I would be tempted by a 12" over a 10" and forget EP's and GOTO that comes with the scope. You will find many cheap EP's for sale on the forums here.
Good Luck with your exciting new hobby

[Startrek]

I’ve had my Skywatcher 12” Goto dob for over 2 years now and I’m 60 years old 68kg wringing wet , plus back trouble since 22 yrs old from a work accident and have no trouble moving it from the garage to my observing location 8 metres away using my Bunnings parcel trolley , admittedly on a concrete driveway. It’s definitely not a remote scope but quite manageable at home. Goto is excellent , spot on every time after a 2 star alignment. Prior to that I had a solid tube 10” dob so nudge nudge all night , gave me the willy’s after a year trying to find objects star hopping, later on I even calibrated the base with azimuth markings and used a digital inclinometer to find objects quicker. You never look back once you use the Goto
Cheers

[doug mc]

I had a GSO 8 from Andrews a few years ago. The smooth mount operation was leaps ahead from Skywatcher dobs i had earlier. Skywatcher may have made improvements since then though. If you have the storage space, putting a dob on wheels fixes the weight issue.

[bluesilver]

I had the 10 inch GOTO version and was happy enough with it.
I found the GOTO to be handy when starting out, plus you can also use it without GOTO if you want.
But the price is around $2,200 from Andrews, so might be a little over the budget.

[doppler]

Another option is to get a solid tube dob and if you want to move to AP you can fit some tube rings and mount it on a EQ mount. I have been using a 10" SW dob in this fashion for a couple of years now on a HEQ5 pro without issue, it's now on an NEQ6 which is a bit better in windy conditions but needs an extra counterweight due to a higher center of gravity. The 10" SW solid tube is lighter than the GSO equivalent, has a Pyrex mirror and has enough focus travel for AP.

Rick

[NightSkyLK]

Thanks for the detailed explanation. Ill definitely have a look into the Nexus DSC. I really didn't know about this and seems to be a good option. I'll keep this in mind If i want to upgrade to a Go-to system.

[NightSkyLK]

Yeah my initial thoughts were to go with the 12" but the size seems to be too big for me. Even in my own backyard i think portability to an extent will matter and in terms of viewing is ther a significant difference between the 10" and 12"? I do remember there was a big difference between the 8" and 10" so im sure on that but not the 10" vs 12" hence my preference on the 10" one.
And also probably gives me more budget to invest on good EPs if I go with the 10" :D:D

[NightSkyLK]

Ah good to hear the GO TO working well. Im also interested on the GO TO but not sure if its worth the extra $1k over the collapsible Dob. I feel like spending that on good EPs might be a better option. But i've seen through GO To ones and it tracks pretty well too so im still inclined towards it.

[NightSkyLK]

Yeah Andrews have a lot of good comments regarding the GSOs and the primary mirror being very good. its the solid tube though so unless its significantly better I think I would prefer the collapsible option of a Dob.

[NightSkyLK]

Oh i didnt know you can manually track it as well. yeah $2200 seems a bit too much for the moment. Once im hooked on this i know ill be spending more on EPs for sure :D:D

[NightSkyLK]

Oh this is interesting. I do want to do AP at some point. I was thinking more in the line of a refractor (ED80) + HEQ5 pro setup without breaking the bank too much at a future stage. Didnt realize you can actually put a 10" tube on a EQ mount and do this.

Is there a significant benefit over putting up a 6" Newt on EQ mount over the 10"? I know the advantage of more light means you can do AP on very dim DSOs but with stacking cant you do the same with a 6" one? More images obviously but im assuming with a 10" tube it would be more troublesome to keep it balanced and track properly?

[doppler]

A 10" tube on an EQ mount is not really beginners stuff, but there are quite a few that do it successfully. A 10" scope has better resolution and a longer focal length so shows more detail and has a larger image scale. Balance is a bit harder to get right with a bigger tube and good polar alignment more important with the longer focal length. I've found that a heavier tube tracks a bit better with a load on the gears. If you do get the bug you will end up with more than one scope as most of us do. My wish list is big but I have to make do with what I have due to budget restraints. A SW ED80 is on my list as is a cooled astro cam, but for now its the DSLR and dob on the EQ mount.

Rick

[RomanEagles]

https://astrob.in/1kpduv/0/I bought the 10" Bintel BT252-B from Bintel when they were in Melb so I've had it for a while...every now and then I'd get it out and look at Jupiter and the moon which was nice. Since lockdown I've put it on a dolly, (OTA is 16kgs!) purchased barlows and eyepieces and a ZWO asi224mc camera for astrophotography. I've take some exciting snaps....learning stacking with AutoStakkert and improving the image with Registax. It's quite addictive. I can clearly see the advantage of an EQ mount and that's my aim for early next year with tax returns and bonus...My OTA is 16kgs so I'm aiming for the Sky-Watcher NEQ6 Pro mount with tracking so I'll be able to take some bang on photos. Anyway...its all learning at the moment!