Quote:
Originally Posted by grantspants
...it says I should collimate the scope
...upgrading the eyepieces
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Grant,
whether to collimate the scope is best judged by whether you NEED to. The easiest way to make this decision is to find a bright star in the eyepiece, get it reasonably well centred, then DEFOCUS a little bit.
You should see concentric rings if the scope is well collimated. If the rings appear badly non-concentric or skewed to one side, it needs collimating.
While you have it out of focus, and looking through the eyepiece, wave your fingers in front of the scope and point to where the centre of the rings has shifted. This will give a clue as to which of the screws on the mirror cell needs adjusting. Usually a quarter or half turn - AT MOST - will produce either a marked improvement (the right way) or deterioration (turned the wrong way).
As for eyepieces... I'd suggest you aim for just three - low, medium and high power.
For your scope, 25-30mm will be the lowest useful power.
The highest power useful is from an eyepiece in the range 5-6mm.
For a medium power, something around 12mm would be good.
Bintel have a decent range of Plossls at $39 apiece, including 6, 12 and 25mm which would be ideal for your scope
https://www.bintelshop.com.au/welcome.htm
(look under eypieces, page 3)
or the Meade 4000 Super Plossls at $59.
Andrews carry GSO eyepieces, 52 degree field of view for $29 apiece, these will easily beat what you have:
http://www.andrewscom.com.au/site-section-10.htm
The sky is the limit with eyepieces, as you will see from the Bintel pages.. What people are paying top-dollar for is extreme field of view (Televue Ethos) - though this may pose other issues.
There's nothing wrong with budget sets - one of the most sought-after sets on
www.cloudynights.com are the Edmund RKE's; while their field of view is quite modest, they were exceptionally transparent and were comfortable to use (with good eye relief). And they are still in production after 25 years
http://www.edmundoptics.com/onlineca...productid=2075