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Old 20-12-2020, 08:02 AM
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Outcast (Carlton)
Always gonna be a NOOB...

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Join Date: Oct 2008
Location: Cairns, Qld
Posts: 1,289
Quote:
Originally Posted by Don Pensack View Post
It's easy to find out the exact magnification of any barlow with any eyepiece:
--Time the passage of a star (any star anywhere in the sky) from edge to edge in the eyepiece. Insert Barlow and time the passage of the same star from edge to edge.
--the ratio of the first timing to the barlowed timing is the magnification factor of the Barlow.

Example: Timing 1 is 4 minutes and 12 seconds. Timing 2 is 2 minutes and 6 seconds. 252/126 = 2X
Thanks Don,

That is a very handy bit of information to know!!

This is what I love about this place, you just know someone will have some great bit of info & is more than willing to share it round.

Thankyou Sir, I will get on to this as soon as I get a clear night...

Cheers
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