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nobody

27 Apr 2015 08:36



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Este cumva vorba de Administratorul jrcrilly de pe Cloudy Nights ?
Nu din alta cauza, dar vad ca sustine acelelasi lucruri, fara insulte si catalogari de genul "neica-nimeni pe CN":

Given that refocusing to accommodate a reducer will necessarily increase the native focal length, the .63X reducer will deliver something greater than F/6.3 at the correct spacing. If your current ratio is F/6.3 or less, your spacing is too large.
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A final ratio of maybe F/7-F/7.5 would indicate a .63X reduction. The SCT isn't F/10 when refocused to accommodate a reducer; it is slower.
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What's confusing is that the native Fratio increases because there's a reducer there. You have forces moving you in both directions at the same time. A final result of F/6.3 requires a greater reduction than .63X . If you decrease spacing to derive a final result of F/7 or a little more, you'll be getting about .63X from the reducer. That's where it is designed to work so that's where it will give the best stars.

VERIFICARE MULTIPLA: http://www.cloudynights.com/topic/475190-sct-focal-reducer-questions/

P.S. Doar un moderator are puterea de a-si impune parerile "cu titlul de litera de lege".