Thread: Primary focal length measurements
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Old 20-06-2020, 10:24 AM
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Merlin66 (Ken)
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Join Date: Oct 2005
Location: Junortoun Vic
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Peter,
As Matt says and I mentioned previously:
""measure the distance to the focuser, then the focuser to the middle of the secondary and finally secondary to mirror ; add these numbers and you have the FL.""
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