Thanks, Ken!
(I'm thinking of ditching my law degree studies for Year 7 maths.... which I failed......
)
Kass
Quote:
Originally Posted by Merlin66
On your telescope, focal length 900mm, the 25mm eyepiece gives a magnification of 900/25 = x36 and the 10mm will give x90 magnification.
A quick rule of thumb, based on general seeing (the atmosphere) conditions is that the max usable magnification is the same number as the size of the telescope - in your case 130mm; that would mean having an eyepiece around 900/130 = 8mm.
(The 4mm eyepiece provided is for the marketing blurb! So the supplier can say - Yeah but it's a x250 telescope!! Rubbish!)
I'd work with the 10mm (x90 mag) eyepiece until you build up some experience - then look for a good s/h 8mm eyepiece here on the forum.
Enjoy!!
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