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When stacking one lens on another for macro shots (often a normal or wide angle on a telephoto ), what determines the maximum reproduction ratio that the combination can do?

rfusca
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1 Answers1

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$$ M = {F_p \over F_r} $$

where

  • \$M\$ = magnification
  • \$F_p\$ = Focal length of the prime lens
  • \$F_r\$ = Focal length of the reversed lens

Source: Peter Forsell's great page about Math for macro photographers.

scottbb
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asalamon74
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