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jester jester вне форума
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Зав. Фотолаб.
 
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По умолчанию 17.03.2004, 12:51

С английским нормально? Вот кусок handbook именно по close-up:
Scale ratio or distance?
The shortest possible focusing distance for lenses, close-up and macro accessories is usually cited as a performance criterion for their macro capability. This value does not, however, reveal much about the im-age size of the subject. A more relevant parameter is the reproduction ratio that can be achieved (i.e. the ratio of image size to object size) or the smallest frame-filling subject size. For example, a 35 mm lens equipped with a B+W NL 2 close-up lens (= +2 diopters), when set at 0.3 m on its focusing scale, at a dis-tance of 14 cm will cover an object size of approximately 11x16 cm at a reproduction ratio of 1:4.5, whereas a 100 mm lens with the same close-up attachment set for 1 m on its focusing scale, at a dis-tance of 35 cm fills the frame with an even smaller object size of 8x12 cm at a scale ratio of 1:3.3.



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