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Old 02-04-2014, 10:43 AM
Ryz (Ryan)
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Ryz is offline
 
Join Date: Mar 2014
Location: Melbourne, VIC
Posts: 22
Quote:
Originally Posted by julianh72 View Post
Ryz,

Can you just confirm your equipment - you have a Skywatcher SW680 8" Dob (1200 mm focal length), with the standard supplied 20 mm and 10 mm eyepieces, and a Barlow (presumably 2x) - is that right? (Reading through your posts, I didn't see a confirmed list of what you own.)

With that sort of gear, you should be able to see a LOT more than through binoculars - higher magnification, and MUCH more brightness (= lots more stars)!

Suggest you start out like this:

I suggest you start in daylight, to learn how things work. (But be careful to not point the telescope at the Sun!) Set up your telescope to point to something on the horizon (or at least 1 km away), and insert the 20 mm eyepiece. A man-made object like a TV tower or high-rise building can make a good test target, because it will have detail that you can make out easily to check your focus is good (steel bracing members in a TV tower, or balcony handrails etc on a building). Just looking at distant tree-covered mountains can be a bit tricky first time out, because it can be hard to see if you have exact focus on "soft" targets like the tree canopy at a long range.

Adjust focus until you see a clear image. (It may not be very stable, as you are looking horizontally through warm air, but it will do to get you started.) If I have your equipment list correct, this will be a 60x magnification, which is a lot higher than typical binoculars (7x to 10x are typical for binoculars). Make a note of where the focuser is positioned, because this is roughly where you will need it for stargazing at night. If you can't get anything like a focussed image in this condition, you may have a problem with the telescope, and you need to resolve this before you move on.

Take the opportunity to make sure your finderscope is aligned at this point, because you will need this to find targets in the night sky.

Now put in the 10 mm eyepiece and repeat. If you are lucky, it will be almost in focus already, but more than likely, it will need a bit of re-focus. This will be a 120x view.

Now take out the eyepiece, put in the Barlow, and then insert the 20 mm eyepiece into the Barlow. This will give you pretty much the same view as the 10 mm on its own, but will almost certainly need some significant refocusing. Now take out the 20 mm and insert the 10 mm into the Barlow, for a 240x view. This is your highest magnification, and may be pretty blurry due to atmospheric effects, but again, you can experiment to see how much refocus is needed.

Swap the eyepieces and Barlow around a few more times, to get the "feel" of how much refocus you will need as you change field of view / magnification.

Now wait impatiently for nightfall.

Pick a nice bright target, that is easy to find, and will show some detail - Jupiter is ideal right now if you have a view to the north-west in the early evening. The moon isn't visible right now, but will start to come back into view in a week or so.

Always start with your 20 mm (low-power) eyepiece, target the scope with the finderscope, and check out the view in the eyepiece. With the 20 mm eyepiece, you should be able to make out Jupiter as a small disc, and you should pick up the 4 moons as well. Soak in this view - you will never tire of it!

Get Jupiter centred, and swap to the 10 mm eyepiece - remembering to refocus as per your daytime experiments. You should now be able to make out some distinct colour banding. Now try the Barlow with the 10 mm - if viewing conditions are OK, you should see it magnified even more, but Jupiter is pretty low right now, so it is very unlikely you will get an optimal view at high power - you may not see much more detail than with the 10 mm on its own.

Now start looking for some other "easy finds" - the Great Nebula in Orion (in the western sky in the early evening) is the biggest, easiest and most spectacular nebula for a beginner, so you can get some idea of what a bright nebula looks like. Again, start with the 20 mm, and only go to higher power once you have taken in the wide-angle view.

Hunt down a couple of star clusters, again starting with the 20 mm eyepiece each time.

With these easy finds under your belt, you now have some idea of what to expect when you start chasing trickier targets. A bit later in the evening, check out Mars (you probably won't see much more than a slightly shaded red disc).

And don't go to bed until you have checked out Saturn in the eastern sky at about 11:00 pm!

Hope this helps!
Play on words here, but you are a star

That's correct in regards to gear. Unfortunately despite very good assembly instructions, the use part of the manual is a bit more vague for someone at my level.

Will keep you guys posted if interested on how I go
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