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High DSB,
Glad you are enjoying the delights of the southern night sky.
A good gauge as to just how good the seeing is would be to check what the lowest magnitude star is that you can see.
The Herald Bobroff Astro Atlas has a set of maps that show the stellar mag's for the whole sky. There are also some desk top planetariums that allow you to print out your own star charts showing the stellar magnitudes, Red Shift being one.
Using such charts check out a small region around the zenith or a region you are familiar with that has a suitable star field. About now the belt region in Orion works well. Use averted vision and see how dim a star you can detect from your chart.
Out here in the far west of NSW, on a Moonless night, the Milky Way throws a shadow. That is, it's glow is such that you, your telescope and the bushes around you throw a shadow.
Also, another very good gauge of how good the seeing is, is to note how close to the horizon you can look, with the naked eye, before the stars start to twinkle. Out here in the winter, often the stars are rock steady almost to the horizon.
Regarding your scope, if it is a truss do you have a light shroud?, if not get one.
Another tip, get one of those blue poly tarps, large enough to setup your scope on with maybe, a table to put your gear on and a couple of fold-up chairs. Use some tent pegs to hold it down. This has several advantages, if you drop something it will be on the tarp and you will be able to find it.
Also while walking around your scope, you and your guests will not be stirring up dust that may end up on your optics.
When ever you are not looking through an eyepiece make sure the caps are on the eyepiece. Did your scope come with a plastic cover that fits over the primary mirror such as comes with the Lightbridge and GSO Bintel strut dobs. If so use it.
The mirrors in your scope reflect light to the optical elements in your eyepiece. It is at the eyepiece that the image is focused. There can appear to be a lot of dust etc on the primary mirror of a scope, but it will still produce nice images.
To actually physically touch the surface of your secondary or primary is akin to an act of heresy. Next time you get this urge go and mow the lawn, wash the car and do some gardening until the urge passes.
If you are indeed determined to clean your mirrors then I would highly recommend you check out the excellent article on washing mirrors in the Articles section of IIS. On this subject let me say that I recently weakened and washed my 16" primary mirror for the first time in 14 years, my secondary is not yet dirty enough to clean. If your scope is new and you are looking after it, it is highly unlikely that it needs cleaning.
A 10" scope is a great instrument, my first scope was 10", you should get stunning views of The Key Hole Neb in Carina with about 16mm - 18mm eyepiece. If you have an eyepiece around 20mm - 25mm and screw in a OIII or possibly a broad band nebula filter the nebula will about double in size.
For 47 Tuc, Omega Cent and the Tarantula in the LMC my favorite view is with an old 14mm series 4000 Meade Ultrawide. Occasionally these can be picked up second hand, fellow IISer Kevnool picked one up on the IIS for sale section last year. In my opinion this is the best eyepiece Meade have ever made.
Just some thoughts.
Regards
Trevor
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