Thread: How do you estimate focal reduction?
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Old 31-10-2007, 09:45 PM
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5ash (Philip)
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Join Date: Mar 2005
Location: Hunter valley. nsw
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How do you estimate focal reduction?
I have taken two photos of a powerpole , the first at prime focus (F10) and the other using a focal reducer.How can i estimate the equivalent focal length using the reducer by comparing the photos. The photos are shown below.
I'd be grateful for some help . regards philip
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Click for full-size image (F10.JPG)
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Click for full-size image (view 3.JPG)
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Last edited by 5ash; 31-10-2007 at 09:45 PM. Reason: spelling
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