#881  
Old 08-09-2009, 02:19 PM
nickatnite (Nick)
Registered User

nickatnite is offline
 
Join Date: Sep 2009
Location: Melbourne
Posts: 7
Hi Guys,

I singed up to the site a few days ago and I just wanted to congratulate you all on the fantastic community feeling that you all generate.

I came here after spending a little time looking through my binoculars at the skies and getting a need to hunt down some info for my next purchase (still undecided).

I'm looking forward to asking some silly questions, and possibly meeting some of you at some gazing events (Snake Valley is looking tempting).

Nick
Reply With Quote
  #882  
Old 08-09-2009, 02:22 PM
erick's Avatar
erick (Eric)
Starcatcher

erick is offline
 
Join Date: Dec 2006
Location: Shoalhaven Heads
Posts: 8,473
Hi Nick! Yep, Snake Valley in October is the place to be - just come down for an afternoon and evening if you want. Eric
Reply With Quote
  #883  
Old 12-09-2009, 08:26 PM
debbym (Debby)
Registered User

debbym is offline
 
Join Date: Sep 2009
Location: Sydney, Australia
Posts: 1
Hello, My name is Debby andI have just joined. I'm looking forward to learning more
Reply With Quote
  #884  
Old 12-09-2009, 08:28 PM
erick's Avatar
erick (Eric)
Starcatcher

erick is offline
 
Join Date: Dec 2006
Location: Shoalhaven Heads
Posts: 8,473
Hi Debby, welcome. What do you want to know?
Reply With Quote
  #885  
Old 12-09-2009, 08:32 PM
jjjnettie's Avatar
jjjnettie (Jeanette)
Registered User

jjjnettie is offline
 
Join Date: Feb 2005
Location: Far Far Away
Posts: 16,726

Hi Debbie!
Reply With Quote
  #886  
Old 13-09-2009, 04:40 AM
stephenb's Avatar
stephenb (Stephen)
Registered User

stephenb is offline
 
Join Date: Sep 2008
Location: all over the shop...
Posts: 2,098
Hi Nick, Welcome!

Welcome to the forum Debbie, Ask away! Do you have any telescope yet? or are you still looking at purchasing?
Reply With Quote
  #887  
Old 15-09-2009, 10:12 PM
Gab's Avatar
Gab
Registered User

Gab is offline
 
Join Date: Sep 2009
Location: Melbourne
Posts: 5
Hi just joined up. Looks like a great site. My brothers and I are keen to build our first observatory, roll off roof type. He has a farm so space/location is not an issue. Is there a "best alignment" for the footprint of a rectangle building in our hemisphere? I was reading John Hicks book"Building a roll off roof obeservatory" and he states that you should position the building to take advantage of South, South/West and West viewing opportunities. This is for Northern hemisphere being a Canadian publication?
Reply With Quote
  #888  
Old 15-09-2009, 10:25 PM
erick's Avatar
erick (Eric)
Starcatcher

erick is offline
 
Join Date: Dec 2006
Location: Shoalhaven Heads
Posts: 8,473
Just a guess, Gab, but I think you would set up so your roof rolled off to the East or to the West.
Reply With Quote
  #889  
Old 15-09-2009, 10:28 PM
Gab's Avatar
Gab
Registered User

Gab is offline
 
Join Date: Sep 2009
Location: Melbourne
Posts: 5
Cheers Eric, We are just newbs, have considerable construction and engineering skills but definitely need to ramp up on our amatuer astronomy
Reply With Quote
  #890  
Old 15-09-2009, 10:32 PM
GTB_an_Owl's Avatar
GTB_an_Owl (Geoff)
bewise betold neverbecold

GTB_an_Owl is offline
 
Join Date: Jan 2006
Location: Terrigal NSW
Posts: 3,627
i would think whatever is your highest horizon should be the direction it rolls

geoff
Reply With Quote
  #891  
Old 15-09-2009, 10:32 PM
erick's Avatar
erick (Eric)
Starcatcher

erick is offline
 
Join Date: Dec 2006
Location: Shoalhaven Heads
Posts: 8,473
Gab, have a more detailed search back through the threads for Observatories. There are threads showing various constructions in recent years.
Reply With Quote
  #892  
Old 15-09-2009, 10:49 PM
Gab's Avatar
Gab
Registered User

Gab is offline
 
Join Date: Sep 2009
Location: Melbourne
Posts: 5
Thanks Eric and Geoff, will do some more research on old posts.
Reply With Quote
  #893  
Old 16-09-2009, 07:42 AM
erick's Avatar
erick (Eric)
Starcatcher

erick is offline
 
Join Date: Dec 2006
Location: Shoalhaven Heads
Posts: 8,473
Try a search for "Observatory" (in the title) in the ATM/DIY forum.

Last edited by erick; 19-09-2009 at 10:26 PM.
Reply With Quote
  #894  
Old 19-09-2009, 09:30 PM
tommycc78's Avatar
tommycc78 (Tom)
Tom

tommycc78 is offline
 
Join Date: Feb 2009
Location: Ipswich, Australia
Posts: 5
Assistance please!

G'day everyone,

I'm having a spot of bother with my brand new Celestron Advanced GT C8-S, and in particular getting my alignment to work.

I've noted an excellent article by Trevor Hand on setting up an equitorial mount here on Ice-in-Space, but to not avail... what am I doing wrong?

Here's the issue:
1. I'm pointing the mount south-centric per Trevor's instructions, and have assumed a correction angle of 11 degrees east of south for my location (Blackwater, Central Queensland near tropic of Capricorn).

2. The minimum latitude I seem to be able to dial up on the scope is approx 26 degrees, despite my location being 23 degrees South, which is making the slew slightly out of kilter with the true track of the night sky.

3. Using a 2-star align, I still note that a tour of the night sky - particularly double stars which should be easy to identify - does not align at all (nothing in the finder scope or in the vicinity after doing a scan of the reason around there).

4. I had a little more success with a solar-system align using Jupiter, but still didn't align with other objects in the sky. Granted at this time of day a lot of the stars in the region are unfamiliar to me (Alpha Centuri and a few of the more recognisable night sky objects have now disappeared behind my neighbours roof some hours ago)




Any suggestions? Any assistance you could afford would be most sincerely appreciated, as this scope is my pride-and-joy, but would be even better if I can get it to work properly (most probably operator error methinks)!

Cheers and thanks in advance for any help you can offer!
Tom
Reply With Quote
  #895  
Old 19-09-2009, 10:24 PM
mithrandir's Avatar
mithrandir (Andrew)
Registered User

mithrandir is offline
 
Join Date: Jan 2009
Location: Glenhaven
Posts: 4,161
Tom,

I've had my C8 almost a year. I'm still getting the hang of getting it aligned within half an hour. Longer if I want to practice imaging. With patience I can get the errors down to under a second.

Quote:
2. The minimum latitude I seem to be able to dial up on the scope is approx 26 degrees, despite my location being 23 degrees South, which is making the slew slightly out of kilter with the true track of the night sky.
Make sure the peg for the mount is over a tripod leg. Mine wasn't. The builtin level is almost certainly wrong. Use a known good spirit level.

You can set the tripod so the top plate is not quite level by making the south-pointing leg shorter. That should give you 3 degrees without too much trouble. As the mount doesn't rotate on the tripod it shouldn't matter. It might complicate polar aligning a bit (see later) because the software expects it to be level but should not make it impossible.

Quote:
3. Using a 2-star align, I still note that a tour of the night sky - particularly double stars which should be easy to identify - does not align at all (nothing in the finder scope or in the vicinity after doing a scan of the reason around there).
Two part answer.

First the finder. It is simplest to get the finder and the main scope aligned during the day. With the mount turned off, centre the image on the C8 at something fairly distant - a distinctive object on the horizon is good. Use the finder thumbscrews to point at the same object. Make the screws firm. They don't have to be tight - that comes later. That will get you in the ballpark. After dark point the scope so that any easy to see object is on the cross in the finder. Move the scope a little with the motor. Rotate the finder tube so the object is back on one of the crosshairs (not the central cross - just one of the lines). Check the object is centred in the C8. Repeat a couple of times until you are happy.

Second the mount. Have you got the latest firmware? The one that has "Polar Alignment" under the "Align" button menu. That lets you adjust the polar alignment on any object. (The older firmware only works in the Northern Hemisphere.) If not you need a suitable serial cable for the hand controller to upgrade both the mount and hand control firmware. You can get the Celestron one, but there is a diagram you can use to make your own. I used a telephone handset cable with a correctly pinned RJ12 to DB9 plug, plus a DB9 to USB cable.

Quote:
4. I had a little more success with a solar-system align using Jupiter, but still didn't align with other objects in the sky. Granted at this time of day a lot of the stars in the region are unfamiliar to me (Alpha Centuri and a few of the more recognisable night sky objects have now disappeared behind my neighbours roof some hours ago)
Get yourself a copy of Stellarium. Configure your location. You can ask it to find objects (F3) and it will rotate the sky to show them to you.

If you have the cable mentioned above, also get the ASCOM driver software and StellariumScope. Then you can see where the scope is pointed, and point the scope at objects in Stellarium. They won't be perfectly aligned until you get the polar align right, but it will get you reasonably close.

You might get some answers from nearer Blackwater. There are a few IIS members in the deep north.

Good hunting.
Andrew
Reply With Quote
  #896  
Old 22-09-2009, 10:18 PM
Ed Croft
Registered User

Ed Croft is offline
 
Join Date: Sep 2009
Location: Noggerup, Western Australia
Posts: 1
Absolute Beginner

Hi,
I was just lucky to receive a 10inch (?) (254mm) collapsible Dobsonian telescope after expressing a desire, as an off the cuff remark when asked "what do you want for your birthday?" I wasn't quite expecting what I was given, though I am rather impressed and delighted. I have started reading some books and been given some advice from a mate of my Fathers, who is a keen astronomer. I have only been able to take my instrument out once in the two weeks I've had it due to inclement weather. My finder scope was not aligned correctly and I had very little idea as to what I was doing. I managed to somehow view a planet, but not well and couldn't keep it in view very long. Unsure which one it was even! I have two eye pieces. A 10mm and a 25mm. Which one gives the highest magnification? I couldn't see anything with the 10mm, though by that stage I was really cold (it was about 1 degree celcius). Thanks Ed
Reply With Quote
  #897  
Old 22-09-2009, 10:25 PM
[1ponders]'s Avatar
[1ponders] (Paul)
Retired, damn no pension

[1ponders] is offline
 
Join Date: Nov 2004
Location: Obi Obi, Qld
Posts: 18,778
Ed. Have a good look through the site you'll find all sorts of information you never thought you needed to use.

If you have a 12 inch dob then its focal length would be around 1500mm. To find the magnification you are using divide the focal length of the scope by the focal length of the eyepiece. eg 1500/10= 150X

Use the largers mm eyepiece to start with (especially when trying to line up your finderscope on a distant tree or telegraph pole) and then once you have found your planet of interest slip in the 10mm eyepiece. You will see Jupiter quite well at that magnification though a 2X barlow would be useful. A barlow multiplies the focal length of your scope. eg 2X barlow give you a 3000mm scope and you 10mm eyepiece gives you 300X (which in most conditions will be a bit much mag.)

Hope that helps you get on your way.
Reply With Quote
  #898  
Old 24-09-2009, 04:20 PM
Pogers (Rick)
Registered User

Pogers is offline
 
Join Date: Jul 2009
Location: Melbourne, Australia
Posts: 5
Hi guys, This will probably sound very stupid to a lot of you, however I am learning as I go along.
I have a celestron 130 and I just recently purchased additional lense and a Barlow. Iím currently looking through a 6mm lens and a 2x Barlow, Iím happy with the viewing however the scope shakes a little and what Iím viewing darts around a fair bit. Any advise how I can limit the shaking? I also find it difficult to adjust the focus as when I do, the scope shakes and the object again darts around and I struggle to focus. Can anyone suggest anything?

Thanks.
Reply With Quote
  #899  
Old 24-09-2009, 04:32 PM
iceman's Avatar
iceman (Mike)
Sir Post a Lot!

iceman is offline
 
Join Date: Sep 2004
Location: Gosford, NSW, Australia
Posts: 36,709
Hi Rick. A 6mm lens with a 2x barlow is just far too much power with a 130mm scope.

You would really only use the 2x barlow with the other eyepieces in your set, like a 15mm or 25mm etc.

All the symptoms you're describing is due to the magnification you're using on a small scope.
Reply With Quote
  #900  
Old 24-09-2009, 04:36 PM
erick's Avatar
erick (Eric)
Starcatcher

erick is offline
 
Join Date: Dec 2006
Location: Shoalhaven Heads
Posts: 8,473
Hi Rick. 6mm eyepiece x2 sounds like quite high magnification. Could you identify the scope a bit better for us - there are a few "130"s in the Celestron range. Is it a basic EQ mount?

And what are you seeing that you are happy with, using that combination?
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 03:14 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Advertisement
EQ8-R
Advertisement
Testar
Advertisement
Celestron RASA
Advertisement
Star Adventurer
Advertisement
Lunatico Astronomical
Advertisement
Bintel
Advertisement
Astromechanics
Advertisement
Astronomy and Electronics Centre
Advertisement