Assistance please choosing new Dobsonian

[tasman (James)]

Hi All,

I'm hoping to get some opinions from members familiar with the dobsonian scopes listed below.

A bit of background - I've used an 8" Skywatcher Dobsonian for the last 6 years and am familiar with there pros and cons. Overall though I like them, and am now in the market to upgrade on my existing setup.

SkyWatcher 12" Collapsible Dobsonian
http://www.myastroshop.com.au/produc...sp?id=MAS-041G

SkyWatcher 10" Collapsible Dobsonian - GoTo
http://www.myastroshop.com.au/produc...sp?id=MAS-041K
These are the two that are within my budget. I'm tossing up between extra apperture and slewing capability.

Have any forum members used either of these scopes?

Thank you for looking.

James.

[glend (Glen)]

Go as large as you can afford, and it doesn't really matter if it doesn't have goto as most dobs can be fitted with pushto systems at a fairly low cost these days and in most cases pushto is faster and lighter than factory goto. Remember that alt az goto systems, like on that dob, will not track objects with accuracy the way an equatorial system will, what they can do is find things - but pushto systems do the same thing. Goto will add complexity, and weight, and motors and controllers are usually the parts that need attention down the track.

Stick some encoders on the 12" and set it up with Sky Safari Pro and a wifi device like Astro Devices Nexus (they also sell the encoders and brackets now), and you will have a Pushto system.

PS, Shop around, check out Andrews in Sydney located here:

http://www.andrewscom.com.au/site-section-10.htm

go to the Skywatcher page and scroll down to your scopes, and find out what each supplier will throw into the deal and how much they will charge from shipping. Being in Tasmania that could be an important cost differential.

You can also get a good 12" dob for much less money if you check out Bintel's Dobs, and they have a shop located in Melbourne. Check out the specs for both, resolution, limiting magnitude etc, there won't be much difference.

http://www.bintel.com.au/Telescopes/...oductview.aspx

[Allan_L (Allan)]

Hi James,
I have used both, but in the reverse configuration.

I currently have a skywatcher 12" GoTo collapsible Flex DOB.
Before that, I had a non-goto 10" Skywatcher collapsible Flex DOB.

I was able to do a side by side comparison of the two at our (mostly) Dark Sky site at Mangrove Mountain). As you can imagine, there was only a small noticeable difference in the detail and brightness of objects in the 12". (eg, you could easily make out the six star in the Trapezium with the 12, but the 10 was not so plain to pick it up).
But I really had to look hard to pick much difference visually, between the two.

GoTo is a real advantage of course, and is worth the extra investment.

The other point is the extra weight of the goto equipment.
As against the extra weight of the 12". I find the extra dimensions of the 12 a little difficult for transport, where the 10 was much easier to handle. I have to admit, I am even contemplating swapping my 12goto for a 10goto just for the easier transport features relevant to my own personal situation.

Finally, on the Skywatcher Flex Dob collapsible DOB itself, I highly recommend it. Much quicker and easier to set up than a traditional TRUSS Dob, and holds collimation really well. Much easier to transport than a solid tube, of course. Good optics. With Pyrex instead of BK7 glass mirror improves cool down times. I really do like the skywatcher (of course this is solely based on just the two that I have owned), I am very happy with them.

Please let me know if you have any further questions.
Regards
Allan

Originally Posted by tasman

Hi All,

I'm hoping to get some opinions from members familiar with the dobsonian scopes listed below.

A bit of backgroun - I've used an 8" Skywatcher Dobsonian for the last 6 years and am familiar with there pros and cons. Overall though I like them, and am now in the market to upgrade on my existing setup.

SkyWatcher 12" Collapsible Dobsonian
http://www.myastroshop.com.au/produc...sp?id=MAS-041G

SkyWatcher 10" Collapsible Dobsonian - GoTo
http://www.myastroshop.com.au/produc...sp?id=MAS-041K
These are the two that are within my budget. I'm tossing up between extra apperture and slewing capability.

Have any forum members used either of these scopes?

Thank you for looking.

James.

[Allan_L (Allan)]

Just a further comment on Glen's posts:
The Skywatcher can be used as push to, goto, or a combination f both.
This is a great feature.
It can make it quicker to get to any object, and it can conserve battery power.

The skywatcher GOTO DOB does "track" items.

I have put Saturn in the middle of the view, left to socialise, and come back several hours later to find it still within the field of view.
What it doesn't do is track equatorially, of course.
So the tracking is not precise enough for astro-photography.
But then again, field rotation from any Alt-Az mount will preclude long exposure shots anyway.

Finally, when I was looking for a goto or push to add on for my 10", I did not come across any low cost systems that I was happy with, or that I thought I could add successfully myself.
Perhaps that is just me.
But I have regularly found it is best to buy systems that are designed to work together in harmony rather than add an aftermarket generic system.
Although I am aware others have successfully done so.

Originally Posted by glend

Go as large as you can afford, and it doesn't really matter if it doesn't have goto as most dobs can be fitted with pushto systems at a fairly low cost these days and in most cases pushto is faster and lighter than factory goto. Remember that alt az goto systems, like on that dob, will not track objects with accuracy the way an equatorial system will, what they can do is find things - but pushto systems do the same thing. Goto will add complexity, and weight, and motors and controllers are usually the parts that need attention down the track.

Stick some encoders on the 12" and set it up with Sky Safari Pro and a wifi device like Astro Devices Nexus (they also sell the encoders and brackets now), and you will have a Pushto system.

PS, Shop around, check out Andrews in Sydney located here:

http://www.andrewscom.com.au/site-section-10.htm

go to the Skywatcher page and scroll down to your scopes, and find out what each supplier will throw into the deal and how much they will charge from shipping. Being in Tasmania that could be an important cost differential.

You can also get a good 12" dob for much less money if you check out Bintel's Dobs, and they have a shop located in Melbourne. Check out the specs for both, resolution, limiting magnitude etc, there won't be much difference.

http://www.bintel.com.au/Telescopes/...oductview.aspx

[rustigsmed (Russell)]

hi james,

i've got a goto 12" SW dob and absolutely love it.
if i ever decide on getting a bigger dob it will have to be motorized like the SW system - it really is handy.

i've even been able to do some deep space photography with the dob.

https://www.flickr.com/photos/80336656@N07/

I'd try and stretch for the 12" goto if you can - but they are big and heavy so perhaps another consideration.

[tasman (James)]

Allan, Glen and Russell -- Many thanks for your input and shared experience.

I have decided to go with apperture and have chosen the SkyWatcher 12" Collapsible Dobsonian. I will try and upgrade this to Go To with the kit supplied separately when my budget allows for it.

Again many thanks for the advice; and great photos Russell, some very impressive astrophotography using the dobsonian! I've bookmarked your gallery and will check it out again when I have some more time to have a proper look through.