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View Full Version here: : GoTo or non-GoTo Dobsonian


guym50
05-07-2013, 03:07 PM
Hi everyone,

I already own a rejuvenated Celestar 8 (new Celestron CG-5 GoTo mount, etc etc) for astrophotography, and I have changed my mind from purchasing a bigger (11") SCT OTA towards a Dobsonian, minimum would be 12", for visual use and ease of setup.

:shrug: I just cannot make my mind up as to whether the Dob should be a GoTo.. I do know my way around the night sky, and I do have lots of printed sky charts to help, so technically speaking GoTo is not essential for me to find an object.

There is a huge price difference between GoTo and non GoTo, over $1000. The only advantage that I see is the tracking ability of a GoTo scope. Is is worth the additional dollars?

I can get a GSO 16" non GoTo from Andrews Comms for $1999. A Skywatcher 16" GoTo is $3299... $1300 difference...

A closed tube non GoTo GSO 12" Dob from Andrews is a comparatively cheap $799. GSO don't make a 14" non GoTo, so the 12", though less powerful than a 14" or 16", is still a good scope for planetary and deep sky visual enjoyment, I think. It is also lighter...

I welcome your thoughts and guidance :)

Thanks in advance

Guy

rustigsmed
05-07-2013, 03:25 PM
Hi Guy,

I have a skywatcher 12" goto and am quite happy. I also have GSO 12" OTA for my new EQ8 and kind of wish i bought a SW OTA instead, collimating is WAY easier with the SW as far as I'm concerned. As for the goto function (although I could find targets fairly easy myself too), I find the tracking really handy and not having to worry about continually moving the tube to keep the object in view. Plus its easy to set up with a simple 2 star alignment.

The skywatcher goto also allows you to move the scope without losing its tracking position which is extra handy. and of course you don't need to use the goto function if you want to freestyle it.

if you can afford the goto, go for it. if its down to going 16" gotoless or 12" goto, thats a tough one, it might depend on if you plan on taking it with you places or where it will be stored as the 12" as you're probably aware is about as big as you can go without needing a step ladder. SW also does a 14" goto but i think the price is close to the 16" so you'd go with that anyway.

I don't know much about the other brands, i think the Orion models might be the same as SW.

here's my flickr page to my photos obtained with my SW 12" goto
http://www.flickr.com/photos/80336656@N07/ including a bit of deep space.

Best of luck :)

glend
05-07-2013, 06:39 PM
I have the 12" GSO (non-goto) (from Andrews) and am very happy with it. If you have it setup correctly (leveled, aligned to north, and with azimuth setting circle and inclinometre then it hits the target everytime, but it helps to have the good GSO 30mm Superview EP with it.

I would not spend the money on Goto, in my opinion it makes you lazy and hinders sky knowledge buildup. There is a big jump in cost from the 12" to the 16" and I did consider that one. Overall I am happy with the 12" and am in the process of working through the Deep Sky Southern Gems.

You can, at a later stage add a motorised base and Goto system but that should not be allowed to delay your enjoyment now.

Allan
06-07-2013, 02:17 PM
Hi Guy,

I bought a GOTO telescope and I can tell you, I will never own a non GOTO again. As you rightly say, the GOTO is not that critical once you get to know the sky, but it is very nice to have and definitely speeds up observing. But what I really like about my Dob is the tracking. There is nothing better than showing a group of people an object that never leaves the FOV. Then swapping eyepieces and filters in and out and still having the object in the same place. I hook my telescope up via wireless to my iPad and drive it from there using a sky atlas app. It sure makes for really fun observing. Good luck deciding, but I know what I would do.

mental4astro
08-07-2013, 11:32 AM
I considered motorising my 17.5" dob a few years back. Went as far as installing an Argo Navis system. But I ditched the whole lot. Two reasons:

* it added a level of complexity that my push-pull scope doesn't have - no power concerns, no extra pieces to forget, no electronics to worry about. I just didn't enjoy the experience. This hobby for me is not a race, & I enjoy the thrill of the hunt. I'm very happy just using charts.

* I actually see more in the EP by physically moving the scope myself. Not a freak thing, but a real physiological response of our eyes at low light levels. I'm not bothered about the need to nudge the scope. I can spend upto three hours at the eyepiece sketching an object, & I'm ok with nudging. I believe it's also made me a better observer, able to find objects easily & see fainter details.

What this also allowed me to do is redirect the money to better EPs. These also give me a wider AFOV, so a longer drift time of the target though the EP.

Don't forget there is a third option, push-to, such as Argo Navis. Systems such as AN can be readily retrofitted to dobs, and can have a much more extensive catalogue of objects & other features than most go-to scopes. They also add very little weight to a dob. Argo Navis is one great system. Yes I sold the CPU, but I've still got the encoders & couplings should I go back to it. That's another thing about Argo - you can buy or sell the system without killing your current scope, & you don't need to use it all the time, it just plugs in & out. Resale value is very high with it too. Oh, it can also be used in a go-to capacity too. You can get as large a dob as you want now, retrofit it with an Argo system, and still be infront $ wise.

Mental.

guym50
24-07-2013, 02:48 PM
:thanx: Thank you all for your recommendations.

Finances allowing, I am definitely leaning towards a Skywatcher Syncscan Goto Dob from Andrews Comms, either the 14", now reduced to $2500, or if I can go further, the 16" for $3400.

Is the extra light gathering power of a 16" over a 14" to be used mostly in suburban western Sydney worth the extra $900?

I welcome your commments and recommendations.

Cheers

Guy