Thread: Review: Eyepieces for PST Solar Telescopes
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Old 26-02-2013, 01:53 PM
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Merlin66 (Ken)
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Location: Junortoun Vic
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Jason,
No. The final effective focal length is 400mm.
The "barlow" on the front of the etalon is positioned 200mm inside focus, and the "refocusing" lens is a 200mm focal length.
We have (400-200)+200 = 400
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