Newbie says hello and asks advice

[deepblue]

Hello Guys

I wanted to introdice myself to you all and ask for your considered advice.

Always wanted a scope as a kid but couldn't afford one and even had the option of doing astronomy at Uni but declined as had other pursuits to follow at that time during the hours of darkness !

Anyway, things have moved on and my interest rekindled by living down in Oz and the availability of relatively cheap (compared to years ago when I couldn't afford one) great quality large aperture reflectors. Like most newbies I am drawn to large aperture to gather the most light and the Dobsonian mount looks easy to use for hopping around.

An thinking of a 10 or 12 in Guang Shen dob and wanted to get a few pointers. I realise the 12 in is large and heavy, but has anyone had experience of moving the 12in around. Is it do-able - I am fairly large and strong with no bad back as yet....

The OTA comes off from the mount, but how difficult is it to take off/put back on the mount?

Also a question on colimaters. The laser variety sounds perfect for the newbie but I have read elsewhere on this site that best not to use them. What type of colimater is best/easiest to use?

Finally eyepieces - what focal lengths would be appropriate for the GS980 to give a good range of magnification and wide field of views?

Oh, I forget to ask where are the best sites for viewing in Sydney? I've been up to Tania Park in Balgowlah Heights where you get uninterrupted 360 views. Light pollution a bit of a problem but don't know how compares to other sites on the North Shore...

Appreciate any help and comment

Cheers

Deepblue

[[1ponders]]

I'll just say :hi: and :welcome: Deepblue. I'll leave the experts to answer your questions ;)

[davidpretorius]

the 12" is fine unless you are a tiny guy ie 5'1" and 50 kgs! The extra $$ is more than made up by the aperture!!!!

Galaxies and nebula are superb in a 12"

Ken (BallaratDragons) has the same scope as mine but in 12" compared to my 10". I was amazed at the sombrero galaxy with the same eyepiece, just different scope.

re collimation, I believe it is a long term learning curve......ie there is simply no easy instant way! get yourself a good sight tube for aligning the secondary and lining up the primary(http://www.andysshotglass.com/Collimating.html a movie to view or http://www.schlatter.org/Dad/Astronomy/collimate.htm), but most importantly, learn to star test(http://legault.club.fr/collim.html)

I am able to use a 4mm TMB in my 1250 focal length 12" scope = 312x magnification. in say a 1500mm, the range may be say 5mm on a good night right up to 31mm or 40mm.

By the way, welcome, a great place to find help

[davidpretorius]

otherwise paul would normally this one www.meade.com/maxmount/ (http://www.meade.com/maxmount/)

[janoskiss]

Depends on where you live and where storage is locate in relation to observing, but almost certainly you would use a 10" more often than a 12".

The 12" is not only more hassle to lug around, but you also have longer wait for cooldown before you can use it. IMO/E the 12" is also more awkward to operate, and sit down at in comfort, due to its sheer bulk. I like to sit and "meditate" at the EP, stare at an object for a good while. Lot more easily done with the 10".

I recently sold my 12" GSO and bought a 10" Saxon aka Skywatcher. Much happier with it. The Saxon also came with Pyrex mirror which seems to do the job, because the scope is very usable after zero cooldown time (turn on fan just to blow off inversion layer) - but it's not winter yet. 10" GSO with all the extras is a great scope also.

[deepblue]

Many thanks for your posts !! And thanks for the useful links
David.

I guess i'm trying to work out if there is a material difference in the images seen through a 10in scope compared to a 12in. Inderstand that the 12in will be better but will I think - wow that's much better !! If difference only marginal then the 10in might by the best option?

[janoskiss]

Best to go along to a viewing night (or several) and see for yourself. And spend some time with both types of scopes see what feels right for you.

[ispom]

welcome deepblue!
I fancy your nick , if it means the deep blue of the sky :) :)


concerning your problem I can say only:
don’t take a refractor,
a own such one, a very good equipment, 4”

but not good for nebula and galaxies….

[Starkler]

A consideration is that a 10" is easily transported in most cars because the tube fits nicely across the back seat. The 12" tube requires a larger car or van and the laying down of seats to transport it.

[rmcpb]

Welcome to IIS Deepblue :)

Geoff raised the clincher between 10 & 12" scopes, transport to a dark site. If you can handle a 12" then go for it but if you cannot get it out to a dark site sometimes you are crippling your observing and would be better off with a 10".

Cheers

[jjjnettie]

Hi and Welcome,
I've got the 10" and for me it is the max. that I would go up to. It's not too heavy to pick up and manouver into the back seat of the wagon.
The views are excellent.
If you want to look through something with more apeture, just cultivate some astro friends with big dobs.

[astro_nutt]

Another Hi! and welcome to IIS Deepblue!!
Like Janoskiss, I have a 10" saxon dob...and it does get plenty of use!!..not too hard to transport around..easy to collimate..but whatever you choose..enjoy!!
Cheers!

[chunkylad]

Hi Deepblue

I have a 12"er, and have no trouble moving it about the backyard, or transporting it to darksky sites. I move it around in one piece - that is, with the OTA still attached to the mount. I use a modified trolley ($20 worth) for this purpose. IMHO aperture rules,:thumbsup: so I put up with what little inconvenience manhandling my behemoth around gives me.

I have also mounted castors to the back of my trolley to load it (lying down) into my van: OTA, mount and trolley together, tied down with occy straps. I think you'd have little trouble putting it into a wagon, provided you have sufficient room between the front seats and the tailgate.

Cheers

David

[chunkylad]

Here's a couple of piccies of my trolley: Not shown are the castors which are mounted on arms at the back of the trolley. these were a later addition.

[Geoff]

Hi, welcome to late, and cold nights brrr in winter.
I compared my 10 inch with my 12 inch and found the 12 inch was better. Not WOW better but "yes I can see the sombrero better" and other deep sky objects. This was done in a light polluted area. I got the 12 inch because a lot of galaxies were very dim with the 10 inch and slightly clearer with the 12 inch. When I drive to the occasional dark area I like the 12 inch. The 10 inch is quicker and easier for me to set up.
Best to go to a viewing night and compare for yourself, listen to lots of advice, and go home confused.
Good luck
Geoff :)

[mickoking]

I own a 300mm Dob, there are no problems moving it about.

[deepblue]

Well guys - thanks for the input - 12in it is !! Seems that most would like to have the 12in but a bit too much hassle for some so they go for smaller scopes. I measured up the wagon and I can get it in and have been to the gym lately so should hopefully be able to handle the extra few kilos !! Also viewing from light polluted skies means the extra inches will come in handy.

Has anyone bought a 12in GSO from Andrews Communications - they offer a better deal/package than Bintel for the same scope. Was the scope a good 'un after collimation? Are they helpful if you have any questions after the sale has been made ?


Just like to say that the collimation video on http://www.andysshotglass.com/Collimating.html

is simply superb and takes 98% of the mystery out of collimation so much happier/confident about that.

Also, where to go for dark skies within 30 minutes drve of North Sydney? I heard the Terrey Hills is pretty good ??

Cheers

Deepblue

[iceman]

You should meet up with us at Kulnura! A group of us meet up at "The Paintball Place" at Kulnura, which is about 1 hr north of Sydney. It's a great group of people, and pretty good skies for being so close to sydney.

There's a sticky thread in the Star Parties forum.

The next one will be the new moon in Feb.

[jonathank]

Hi DeepBlue,
I can't help you but welcome aboard.
:welcome: :welcome: :welcome: :welcome: :welcome:

[chunkylad]

I bought my 12" Dob from Andrews' Comms, and it arrived very promptly and in excellent condition. You will need a long cheshire sight tube to collimate, but I find mine stays fairly well collimated.

If you're looking for after sales service rather than the best price, then perhaps Bintel might be a better bet. From personal experience, I found all the information I needed was either provided by the members of this forum, or links steering me in the right direction were given. This made it unnecessary for me to rely on the supplier of 'scope for such advice and/or service. I'm not bagging Andrews' by any means. Their service was great, and I got a right angled finder instead of the straight through type I was expecting. Bonus!!!:D I just didn't need any help from them once the deal was done, except to purchase some other odds and ends.

And 'yes', the 12" Dob from Andrews' Comms is a good'un. :thumbsup:

Good luck.

Dave W