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Old 20-02-2008, 01:00 PM
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Geoff45 (Geoff)
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Geoff45 is offline
 
Join Date: Jul 2006
Location: Sydney
Posts: 2,631
There is a lot of confusion about "magnification" If you look at a typical image of the moon at prime focus it will be about a centimetre or two. Since the real moon is about 3000 km in size, there is no magnification, in fact quite the reverse. The image is much smaller than the real thing. Magnification makes more sense when you are using an eyepiece, because then you are comparing the apparent angular size you see through the eyepice with the real angular size that you would see if you looked at it directly. Keep both eyes open and compare the image through each.

When you make a picture, things get complicated again. Obviously an A3 picture is twice the size of an A4 pic of the same object, so is twice the magnification. It also depends how far away you hold the picture. It looks smaller as you move it further away.

Hope this has confused everybody.
Geoff
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