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Old 27-06-2018, 10:50 AM
TwistedRider (Drew)
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Beginnings and things

**Warning: Newbie Alert**


Hi all,

Doing a lot of reading and being very very restrained. So haven't raced out and bought anything yet.

Have had some good advice, and hoping to get look through a few scopes soon.

A few questions (all based on theory so far) while looking at shiny catalogues with new toys..

Interested in a mix of both Planetary observation and well as Nebula etc.

1 Dobsonian or Netwonian?
What's the man different/ benefits for each (other than the mount
The Dobsonian looks simpler, but also more cumbersome to transport? Newtonian on a tripod looks like it might be easier to move?

What is the functional or viewable difference between these types?

2 Other than a scope/mount/stand etc what other items are considered essential? I have no practical understanding of eyepeices etc other that they magnify or alter a field of view?

3 I have an interest in using a GOTO mount eventually. Is it worth looking at having this to start with or is it best to get this later as an add on or upgrade?

Looking at what is available at my budget level and depending on mirror size, a goto "may" be possible. My personal view is to get a better performing scope 1st and worry about fancy mounts later.

Still trying to get my head around aperture and focal length, I'm just assuming wide and long makes better images at this stage

Lots of newbie ramblings I'm afraid.

Let the discussions commence
Thanks in advance.
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Old 27-06-2018, 12:09 PM
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gaseous (Patrick)
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Hi Drew, congratulations on your restraint! In response to your questions:


1. The mount is the only difference – the Dobsonian is just the style of mount, the tube itself is still a Newtonian, and should be more or less the same regardless of the mounting system. The dob is possibly a touch more cumbersome to transport, but if you’re only interested in visual, I can’t see the point in lashing out big dollars for a tripod/mount sizable enough to support a decent sized Newtonian. Dobs, particularly non-goto dobs, are as easy as pie to use – just plonk it down, collimate it, and away you go. The larger the dob, the more time you should allow for the mirror to cool before expecting optimum performance, but that’s another issue.

2. Telescopically-essential to me would be a few decent eyepieces and a nebula/narrowband filter of some description, and maybe a polarizing filter if you plan on looking at the moon. I won’t go into eyepieces here, as every member will have their own opinion as to what constitutes “essential”, and there are a couple of reasonably current threads on good eyepieces for those just starting out. Viewing-session essential for me would be a decent table to lay your stuff on, a comfy chair, red torch/headlight, collimating laser/eyepiece, and some type of planetary software on your phone/tablet to get you familiar with the sky.


3. I would recommend goto if the budget allows, although learning your way around the sky as well as learning how to align/use a telescope can be a steep learning curve. For me, once you’ve used goto, it’s hard to go back to manually slewing around, although manually finding objects does tend to teach you the general layout of the sky much better. Each to their own - I love my goto.


4. The focal length of a scope will determine the magnification achieved by a particular eyepiece. The formula for this is:

Telescope Focal Length / Eyepiece Focal Length = Magnification.

So a 1200mm FL scope with a 20mm FL eyepiece will give you 60x magnification. An 1800mm FL scope with the same 20mm eyepiece will provide 90x magnification.

Aperture has nothing to do with magnification, it’s just the width of your mirror (in a reflector) or objective lens (in a refractor). The larger the aperture, the more light you’ll gather, and the brighter/clearer things will look, which is particularly relevant if you’re hunting nebulae and faint galaxies. A lot of beginners drift towards an 8" dob as it combines good light gathering with reasonably use and transport.


If you plan on getting into photography, then basically disregard 95% of what I just wrote.


Good luck!
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Old 27-06-2018, 12:51 PM
TwistedRider (Drew)
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Thanks for that.

So far i've been looking at an 8"-10" dob, or about a 200mm tripod Newt.

Goto looks to be an option on the dobs in my budget (Just). But very little for eye pieces etc... unless someone has an awesome deal for me

I've been playing with and doing "naked eye" observations with Stellarium and a little "Cartes du Ciel"

"Crux" isn't too hard to find

Would love to get some photos of what i'm seeing at some stage but i think that's a whole other game.
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Old 27-06-2018, 01:25 PM
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gaseous (Patrick)
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A new dob will often come with a couple of fairly entry level eyepieces to get you started, so you don't need to make major decisions on eyepieces straight away.
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Old 27-06-2018, 01:39 PM
TwistedRider (Drew)
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Thanks Patrick.


So far i think im looking at an 8" Goto Dob or a 10 inch dob without the gizmos.


Other than alignment or light bleeding in, any issues with Collapsible Dobs? Figure a shroud should stop the light issues ok.
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Old 27-06-2018, 01:54 PM
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Yeah I'd consider a light shroud a worthwhile investment. For my 8" dob I also got a set of 3 adjustable furniture legs from bunnings to make leveling easier. Not really an issue for non-goto, but pretty critical for goto (as is a spirit level).
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Old 27-06-2018, 05:44 PM
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Hey Drew, like you I have just got into this with a going for a new scope, I have just purchased a 10" collapsible Skywwatcher Dob, unfortunately I don't have the restraint you have and been on a bit of a spending rampage, loving my purchases so far.

I also considered the Goto option but decided for my first real scope that I would not worry about it for now and spend the money on other accessories like a light shroud (I think having a shroud is definitely worth it), eyepieces, collimator etc.

Of course as legend goes, when you buy a new scope it comes with a complimentary week of cloudy nights, I assembled my Dob and literally it started to rain within 10 minutes.

End of financial sales are on at the moment with the major online telescope shops and it appears I got the 10" Dob at what appears to be a good price, just sayin!
Good luck and enjoy whatever way you go.
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Old 27-06-2018, 06:03 PM
TwistedRider (Drew)
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Hi Rob,

The coloapsale Dob is also sitting at the top of my list right now. Still thinking about the goto.

The Sales are very tempting indeed. I've almost bought online twice today


All going well, I wont have to wait to much longer before i make a choice.



Cloudy nights and cold weather...
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Old 27-06-2018, 08:04 PM
raymo
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Two points; if you are very likely to get a GoTo Dob at some not too distant
time, get it now[while sales are on] as adding the GoTo kit to a Dob is
more expensive than buying one in the first place.
Skywatcher collapsible Dobs do not need collimating every time you use
them; they hold collimation very well indeed. I tweaked mine every few months.
raymo
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Old 27-06-2018, 08:53 PM
TwistedRider (Drew)
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Thanks Raymo

Yes I noticed the upgrade kit was rather pricey

My wallet is in danger of flying open each time I look I look at scopes but should be good to pick something up at the last moment on the weekend.

Then I shall commence the ritual sacrifices for clear skies. ��
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Old 28-06-2018, 08:41 AM
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sil (Steve)
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I think from your jumble of wishes you want something that does everything (doesn't really exist) or you want several scopes (which is what we all end up with). Really nail down what you want. Taking images really isnt as simple as attaching a camera and pressing a button. Get some experience at the eyepiece of various scopes first so you get an understanding of what to expect. You wont see bright colourful galaxies and nebula like whats seen in photos through an eyepiece except on very very large scopes. Typically off the shelf telescopes the OTA (optical tube assembly) is the strongest part of the package while the tripod mount and included eyepieces the weaker. If imaging is really your goal then you need an equatorial mount and its the super critical part of the system to get right. As an imaging system is usually spending hours doing its thing and you cant touch it most people use a dob for a visual scope. I would say an 8" dob (non goto) will be of lifelong use and will teach you much of the considerations before delving into an imaging system. You can of course image with a dob but there are limitations off the bat. Just avoid a newtonian on a manual EQ mount as its more likely to kill your interest completely. An 8" dob will give you amazing views, teach you the issues of finding a target in the sky. Go a 10" if you like i guess. Either way eyepiece upgrades you can look at down the track any time as it should come with a few to get you started.
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Old 30-06-2018, 01:45 AM
TwistedRider (Drew)
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Well, any further financial restraint is gone.


10" Goto colapsable dob has been ordered.
Took advantage of the current sales and offerings.


Now the waiting begins.
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Old 30-06-2018, 07:28 AM
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RobNevyn (Rob)
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Congrats, you know this is just the beginning right? Lots of cool accessories and EP's to look for now.
Let's hope you have better luck than I did with the delivery, my tube arrived in 4 days and then the base arrived 5 days after that.
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Old 30-06-2018, 09:27 AM
TwistedRider (Drew)
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Thanks Rob,

Yes, I'm afraid this will be an ongoing adventure

Certainly have a few items I need to get. Dew heaters and upgraded finders cope.

Hope mine is not delivered that far apart.
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Old 03-07-2018, 01:17 PM
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sil (Steve)
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You read the fine print that says All telescopes come included free with six months of cloud cover? Planisphere, redlight torch, comfy viewing chair and your set for exploring new eyepiece purchases. I've no doubt you'll just love the dob and eyepiece upgrades will give it a new lease on life later on. Ease yourself in though, relax and enjoy at your own pace so much great stuff up there to look at. Keep in mind Jupiter Saturn and mars are all good to look at right now but are gradually going west so while they are in season make the most of them! They are always breathtaking in the eyepiece even years later, they dont really get old to look at, (then you start observing feature changes over the years).
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Old 03-07-2018, 11:53 PM
TwistedRider (Drew)
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It's on backorder

Have a nice shiny planisphere and a moon map though.

Hoping it arrives in time to at least get a decent look at Mars
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