Thread: DIY Barlow
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Old 13-08-2020, 12:25 PM
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Merlin66 (Ken)
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Join Date: Oct 2005
Location: Junortoun Vic
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You don’t mention the focal length of the Barlow lens.
You can measure this by marking a card with a circle twice the clear aperture of the Barlow lens.
Point the lens towards the Sun, when the image fills the circle, the spacing is the focal length.
To get x2 magnification the eyepiece/ camera should be positioned at 1/2 the Barlow focal length behind the lens.
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