First post, first question, first scope.

Night Owl · #1 12-01-2008, 12:32 AM

Good evening all. My first post, and my first question, about buying my first telescope.

I'm finally going to do it. After years of avoiding buying absolute land fill scopes in department stores and unethical camera shops etc. I've lived in country Victoria most of my 44 years of life, 60 km from any major light pollution, and its time I stepped up from waving the 10X50 Pentax binos in the dark. I've done some research and I've finally reckoned that a GSO 12" Dobs is the best 'bang for my bucks".

What do I need to get going and keep going with it? And what can I do without?

Cheers.

cahullian · #2 12-01-2008, 01:28 AM

Hi Night Owl welcome to iceinspace.
I think the scope comes with some not so good eye pieces, but you can still see ok through them. I suggest you get a collimation tool for starters, a planisphere. red tourch, X2 barlow for planetry use. That should see you right for a while. This hobby can get out of hand when it comes to things you need. The important thing is to get out and have a blast.

Gazz

Nevyn · #3 12-01-2008, 01:30 AM

There will be plenty of thingame jiggers you can and will add, but definately get something for collimating. Mine was out enough to make my first two sessions very dissapointing

I eventually bought a laser collimator and find it easy to use especially after watching this vid http://andysshotglass.com/Collimating.html
Eight AA batteries for the fan and you should be enjoying your first night out with the new scope. SHOULD be, but it will cloud over and most likely rain for a week or two

Cheers Brad

cahullian · #4 12-01-2008, 01:35 AM

Ha Ha Brad your not wrong. I can see the clouds arriving as I type...

Gazz

Hagar (Doug) · #5 12-01-2008, 08:54 AM

Things I would look at purchasing:
1. Collimating tool (Laser)
2. Right angle finder scope if it doesn't come with one. The straight threw finder is pretty dificult to use.
3. A 30 to 40 mm 2" EYEPIECE lets you see the whole big picture.
4. Laser pointer and bracket. Makes pointing even easier.
5. Good quality EP's as the ones supplied are near on useless.

Hope this helps.

chunkylad (David) · #6 12-01-2008, 09:01 AM

Hi Night Owll and

.

As has been mentioned: a Cheshire collimation tool, a red torch and a planisphere are a good start. I would add a copy of "Astronomy 2008" to that list. This will give you a month by month guide to what's happening in the Aussie night sky.

About your proposed 12" Dob: I would presume that you have read the many threads in this forum about 'scope choice, and the pros and cons of such a large unit? IMHO, you won't be sorry for the the extra aperture of the 12" over its smaller cousins, as long as transport in the car and around the yard is not an issue (I modified a standard two wheel trolley to suit my dob).

Some tips when ordering your dob: You really should specify a 'right angled' finderscope over a 'straight through' type: this will be much easier to use. Most dobs now come standard with a cooling fan - this is a must, as is a Crayford style focusser. A red dot finder is also a good investment, but not essential straight up.

The GS plossl eyepieces that come standard equipment these days are NOT the poor quality items some would lead you to believe. Sure, they're not premium eyepieces, but they will suffice to get you started and generally give sharp, clear images.

There's plenty of things to spend your hard earned cash on in this wonderful hobby. The items listed above will give you a better-than-average start for a modest outlay.

Personally, I think the best piece of advice I can give is to get to know the night sky, and how to get the best out of your equipment, before spending wads of cash on more expensive eyepieces etc etc.

Good luck and enjoy!

Sammas · #7 12-01-2008, 09:04 AM

Not speaking from a great deal of experience here, just reflecting on my own experiences... the 12" will show you a lot of dim things, and the GSO scopes do seem to be a good way to go.

The only thing I'd warn you about is that the 12" is physically quite large. I have an 8" GSO dob and it's quite big - you don't really appreciate the size until you grab it with both hands (I knew the dimensions before I got it, but I didn't appreciate the volume

. Given that you live under dark skies, transportation probably isn't a huge issue for you, but moving it from inside to outside might be enough of a pain to make you decide to stay indoors on those nights where you're not really fired up. You can still see a lot through an 8" or a 10", but if size doesn't matter to you, obviously you'll still see more through a 12". I have been extremely happy and impressed with what I can see with my 8".

On the eyepieces - the ones I got with my scope from Bintel were fine. I have three plossls - a 9mm, a 15mm and a 2" 28mm. What you are looking for is ease of viewing and clarity of images. Stars should be dots (not fuzzy) and it should be easy to see stuff when you look through the eyepiece. A lot of cheaper eyepieces are hard to look through because your eye has to be in just the right spot to catch the light. With better eyepieces it's less straining to see and you'll see more.

I'd get the scope first, check the eyepieces out over a few nights of viewing and then decide what more you need. Personally, I've decided to get a Barlow because even with the 9mm eyepiece Mars is only a small disc (in my scope the 9mm eyepiece gives me around 130x I think).

I also got a laser collimator. I'd get some kind of collimator right off the bat because you'll probably want to check the scope is collimated when it arrives, and if you suspect it isn't you don't want to wait a few days for a collimating tool - I've heard the 12" models go out of collimation pretty readily (ie: the two mirrors inside the scope become slightly mis-aligned).

xelasnave · #8 12-01-2008, 09:48 AM

Welcome from me..you have made an excellent purchase... if you can buy something that controls the weather go for it ...but just get out there when you can ... fit a shock strap so it does not fall over if you change weight distribution with different ep's or barlow addition..
get a trolley is the best first thing so it is easy to move in and out and a safe storage when not in use.
best wishes
alex

Night Owl · #9 12-01-2008, 10:49 AM

Quote:

Originally Posted by Nevyn

SHOULD be, but it will cloud over and most likely rain for a week or two

Cheers Brad

Not wrong! A mate of mine bought a 12" LX200 and I swear every night that he / we could have been out was either cloudy or raining. I ended up calling his scope "The Cloud Magnet" and have asked him to leave it in his back yard so the drought will break!

Night Owl · #10 12-01-2008, 11:35 AM

Thanks for all the advise folks. I have taken it on board and now have one Guan Sheng GS-980 300mm x 1500mm 12" Dobs on the way straight to my door (should be here Wednesday).

Comes with right-angle correct image 8 x 50 finderscope.
2" Crayford style microfocuser with 10:1 fine focusing and a 2" to 1.25" adaptor.
Cooling fan.
GSO 6mm, 9mm, 15mm and 25mm 1.25" Plossl eyepieces.
And a SP32mm 2" eyepiece.

Also took your collective advice, and ordered a return beam type laser collimator, as well as a 2.5x magnification, 1.25", fully multi-coated,3 elementapochromatic Barlow.

I said to the good wife I wouldn't spend more than $1K on a scope (whispered under breath "At first"...), and thanks to the good people at Andrew's Communications, and the best value for money apeture I could find available, I have come in $3.00 under budget!

Oh baby, I can't wait to look at the Sun with it.

Night Owl · #11 12-01-2008, 11:46 AM

hey xelasnave, You're right. Gravity doesn't suck. I worked it out late one cold night after a bottle of Stones Mac Green Ginger wine!

What is happening is the universe is expanding, and everything in it, and gravity is everything simply catching up with everything else, and here on earth the ground is catching up with us at 1G!

Well hey, it works for me, and nobody has proved me wrong...yet!

chunkylad (David) · #12 12-01-2008, 01:50 PM

I use a barlowed laser to collimate my 12". Obsession telescopes have a great article on laser collimating using a barlow lens.
http://www.obsessiontelescopes.com/l...ml#Collimation

This method negates the inherent slop between the laser and the focusser (slop=inaccuracies in collimation).

Enjoy your 'scope. I know I have mine for the past 2 1/2 years!

GrahamL · #13 12-01-2008, 02:00 PM

good luck with your scope

..I'd grab a telrad as well ..its a really
usefull tool http://www.backyard-astro.com/equipm...ad/telrad.html

Quote:

Oh baby, I can't wait to look at the Sun with it.

I'm guessing thats a tongue in cheek comment

but it has to be said all the same .."never look directly at the sun" ..without the appropriate
equipment and filters to do so ..I wonder if a 12" would focus enough light to burn a hole clear through the back of your head as well ?..have fun a 12" is a great sized scope

Nevyn · #14 12-01-2008, 03:58 PM

Quote:

Originally Posted by nightstalker

good luck with your scope

..I'd grab a telrad as well ..its a really
usefull toolhttp://www.backyard-astro.com/equipment/accessories/telrad/telrad.html

Yes, grab a Telrad! I'll be getting one for myself as soon as my wife forgets about the binoculars I just bought

. A Telrad will make your evenings out with the scope much less frustrating.
At the moment I'm playing around with a 12v mains adaptor for the fan, seems to work ok but the interchangable pin is a little long for when the scope is pointing near to the zenith.
With all said, you're in for a lot of enjoyable nights. Have fun!
Cheers Brad

Night Owl · #15 12-01-2008, 06:50 PM

Quote:

Originally Posted by Nevyn

Yes, grab a Telrad! I'll be getting one for myself as soon as my wife forgets about the binoculars I just bought

. A Telrad will make your evenings out with the scope much less frustrating.
At the moment I'm playing around with a 12v mains adaptor for the fan, seems to work ok but the interchangable pin is a little long for when the scope is pointing near to the zenith.
With all said, you're in for a lot of enjoyable nights. Have fun!
Cheers Brad

OK, I get it. It is exactly like a reflector gunsight from a WW2 fighter!

http://www.youtube.com/watch?v=Blem3FlkaMc

Next question is where do you recommend I get one from? A Telrad that is!

GrahamL · #16 12-01-2008, 07:06 PM

http://www.sdmtelescopes.com.au/shop/index.php
lists @$79 same as bintel .. pete does have free postage ..afaik

Night Owl · #17 12-01-2008, 10:47 PM

Quote:

Originally Posted by nightstalker

http://www.sdmtelescopes.com.au/shop/index.php
lists @$79 same as bintel .. pete does have free postage ..afaik

Nice, looks like one of these!

http://cgi.ebay.com.au/eBayISAPI.dll...m=330201998219

except you can "Buy it now" for $9.95!

chunkylad (David) · #18 13-01-2008, 10:16 AM

This item is a red dot rifle scope. I have no idea about its suitability for astronomical use. ie - the red dot it projects may be ok for large objects at 2oo metres, but what about a faint fuzzy at infinity? Some of their other products quote 4 m.o.a. for the cross section of the red dot.

Most good red dot astronomical finders us holographic concentric rings, not just a single dot.

Below is a quote from the ebay ad:

This is an innovative, easy to aim sight for someone who likes to shoot quickly or at moving targets.
When turned on, a red dot appears on the wide angle screen.
What you need to do is to put the dot on your target and fire.

Red Dot Sight
Fits all 3/8 Weaver Mount
Fully Adjustable Windage & Elevation
Perfect for Paintball, Airsoft, Rifle, Pistol with Standard 3/8 sight rail.

A Telrad or Rigel Quickfinder may cost eighty odd dollars in this country but they are a very good investment. Plus they are designed for use with your telescope.

Just my two bob's worth

Cheers

Night Owl · #19 13-01-2008, 12:02 PM

Quote:

Originally Posted by chunkylad

This item is a red dot rifle scope. I have no idea about its suitability for astronomical use. ie - the red dot it projects may be ok for large objects at 2oo metres, but what about a faint fuzzy at infinity? Some of their other products quote 4 m.o.a. for the cross section of the red dot.

Most good red dot astronomical finders us holographic concentric rings, not just a single dot.

Below is a quote from the ebay ad:

This is an innovative, easy to aim sight for someone who likes to shoot quickly or at moving targets.
When turned on, a red dot appears on the wide angle screen.
What you need to do is to put the dot on your target and fire.

Red Dot Sight
Fits all 3/8 Weaver Mount
Fully Adjustable Windage & Elevation
Perfect for Paintball, Airsoft, Rifle, Pistol with Standard 3/8 sight rail.

A Telrad or Rigel Quickfinder may cost eighty odd dollars in this country but they are a very good investment. Plus they are designed for use with your telescope.

Just my two bob's worth

Cheers

I've used red dot reflector sights on rifles and pistols before, and the dot is usually 1 MOA at 100yards, which = 1 inch at that range. And for $9.95 I don't think it will cause any damage mounted to a Dobsonian!

edwardsdj (Doug) · #20 13-01-2008, 12:39 PM

Collimation is critical for f/5 scopes. If you find collimation is a chore using screwdrivers, there are collimation knobs available that you can just turn with your hand. Personally I find these as important as a collimation tool as they can turn collimation from a rarely performed chore to something you are happy to fine tune before each session.

I got my "Bob's Knobs" for my 12" Lightbridge from BinTel. Collimation is so much easier without tools and the stiffer springs in the kit allow the primary to hold collimation at all altitudes. They were a bit pricey at just under $100 as I recall for primary and secondary knobs and stiffer primary springs.