Quote:
Originally Posted by shaneaust
I can see stuff like Saturn etc but only very small. Is that becuz of the limits of the scope, or my EP, do u reckon?
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Ok,
We've dealt with eyepieces and improving the mount. Now we'll deal with the optics.
Collimation 
OOOH...! Nasty, nasty WORD. Collimation ONLY means the process of aligning the optics. The word is what scares most people because they are 1, not familiar with the word, & 2, a Newtonian's optics is not something people encounter everyday. BUT take away the fear and it is just tweaking a pair of mirrors.
It can be a confusing thing to do at first, and in reality if you can see an image through your scope without tweaking the optics, then the scope is working. It's got a "black eye", but it works.
However, if you do take the time to learn the process, then you will be making sure that the scope is working to its very best, and the scope is giving you the very best image it possibly can, which when you think about it you didn't by that scope for an ordinary image, but a good image. If the optics are not aligned, the image will appear smeared to one side, not sharp in focus, and the stars will not be pinpoints of light, but ballooned out*. Take the moment to align the optics, and the image will be sharp and clean.
I won't go into collimation here. Not when someone else has already done a fantastic job. Look at
Astrobaby's collimation of a Newt site. It goes through the process very well and gives tips on helping newcomers to the process. That site also shows that you can carry out the collimation process with very modest gear through to as much money as you care to throw at it, but if you take your time and understand the process, that modest bit of gear will leave your scope performing just as well as any other bit of gear.
Some people get put of by Newt's about the need to look at the alignment or collimation of their scope every time they set up. Thing is a Newt's optics are held in place essentially by springs (for a reason), and vibrations or the set up and take down of a collapsible type scope will see things shift. Once you get the hang of collimating, it becomes something that you do out of habit and understanding. It will take only a moment, and this moment of TLC on the scope will leave it humming at its very best for you, which is what you want in the first place.
The purpose of this post is to help you see that there are a bunch of little things that go into using an maintaining a dob, and a Newtonian for that matter. Astronomical telescopes are not the same thing as a handheld pirate thingy. They are a bit more sophisticated because their application is a very niche one, and a VERY demanding one from the optics. It then comes to you on how involved you want to get
Alex.
* Eyepiece selection can also be a reason for ballooned or bloated stars. I'll talk briefly about this next.