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Tom Hancock
26-11-2011, 05:34 PM
I just bought a 10" Dob and has been spending a few evenings getting use to it.
My main problem is, pointing the Dob at an object I want to observe but usually end up not quite sure if I am looking at the right thing.
I am practising on Jupiter which is an easy target to find and align, considering it is so bright but Deep space objects are another thing!
The other night, I aim it at the Lagoon nebulae but ends up not sure if I am looking at it?Also, I find it is not easy aiming the Dob at DSO.
Is there any way, to improve my confidence and aiming technique?
:sadeyes:

barx1963
26-11-2011, 06:35 PM
Hi Tom
There is no substitute for practice. IMHO if you are using a manual Dob, there is no substitute for a good star chart. I use Uranometria Vols 1 and 2. Very detailed maps and you find them invaluable in locating objects. A set of star charts such as these http://www.bintel.com.au/Accessories/Books--Charts-and-Software/Star-Chart-Laminated---CD-ROM/655/productview.aspx
help in orienting yourself and finding the bright stars needed to get you close so you can then use the U2000 charts.
Sky Atlas 2000 is also highly recommended but I have not used them.
I also use the Deep Sky Observers guide as a guide to objects to look for.
But remember, there are no shorts cuts to learning to navigate manually, only practice!

Malcolm

jjjnettie
26-11-2011, 07:48 PM
A night or two out with an astro club will push you in the right direction.
As Malcolm said, nothing substitutes for practice. :)
Omega Centauri and 47Tuc are big and bright objects to turn the scope to and fine tune your finder scope.

astrospotter
26-11-2011, 08:41 PM
Most of the right things have already been mentioned but I would add that start the night with a Telrad sight adjusted on some bright star so you know the sight is right on the money. Practice is also fun by the way as a lot of the fun is in the hunt. Just dont hunt for really dim things till you get used to finding brighter things to avoid discouragement.

I enjoy and feel a telrad sight is a must because you can often find bright naked eye stars nearby many targets and position the telrad outer edge or middle circle relative to bright stars then you are likely to be close. Then start with a low power (for you try to have a 32mm plossel or other lens for finding). Once you find the object in that, perhaps recognizing semi-bright stars seen in an atlas, only then do you pop in the 9mm or higher power eyepeice.

You do need some charts like was also mentioned and I would ditto the SkyAtlas 2000 OR if you want a smaller more manageable atlas that shows all the main objects get Sky and Telescope Pocket Sky Atlas. Both have full sky coverage for pole to pole observing. You do need charts of some sort be it printed out beforehand or whatever.


Then go for the bright ones like have been mentioned like Omega Centauri and 47 TUC. You cannot go wrong with looking for Orion nebula because it is right by some naked eye bright stars below the 'belt of orion' and would be a real treat in a 10" scope.

I would also throw in Ngc2561 or other big open clusters because they are more obvious when you find them. Since you can see from a dark area outside of town the LMC and the SMC it would be very fun to find those and browse. The bright showpiece in the LMC is of course the Tarantula nebula. So once you find the LMC poke around within that beast and you are sure to stumble on the huge nebula that can be seen without a filter.

Enjoy the scope. 10" is a really nice size. Portable but still has a lot of light gathering ability and is easy to swing about and move.

Paddy
29-11-2011, 03:53 PM
Ditto to Malcolm's, Liz's and Mark's comments. It helps a lot to have someone show you around the sky. It also helps to have a Telrad to point the dob in the right direction - very hard to do just by lining up the tube. Good star charts help. I also found as a newbie that the Atlas of the Southern Night Sky (http://www.iceinspace.com.au/46-444-0-0-1-0.html) was a good combination of charts with suggested targets and images of the targets so that you know what you're looking for. Wikisky (http://www.wikisky.org/) and the Digitised Sky Survey (http://archive.stsci.edu/cgi-bin/dss_form) are also good ways of finding images that will look a bit like what you see through the scope. (And Clouds of Magellan (http://cloudsofmagellan.net.au/) of course if you're after objects in the Magellanic Clouds.)