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Old 19-01-2007, 10:38 PM
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davidpretorius
lots of eyes on you!

davidpretorius is offline
 
Join Date: Jun 2005
Location: Launceston Tasmania
Posts: 7,381
Quote:
Originally Posted by deepblue View Post
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?
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
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