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Image: MacroPlusRetrolens

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Description: The DSLR camera Pentax K-7 with macro lens Tamron SP AF 90 mm F/2.8 Di MACRO 1:1 and wide-angle lens smc Pentax-M 28 mm F/2.8 installed in "reverse position", using a coupling ring between both filter threads. This combination allows a three times higher magnification (3.2:1) compared to the macro lens alone (1:1). The focal length of the camera-mounted lens – 90 mm, in this case – is crucial to the magnification ratio (calculation is 90:28 = 3.2). It doesn't need to be a real macro lens, any other telephoto lens with that focal length has the same effect. The usage of a tele lens of 300 mm instead would even lead to a magnification of 10.7:1 (theoretically). In order to achieve a larger depth of field, the aperture ring on the reversed lens should to be closed as far as possible (so, it's very useful to have one there!).
Title: MacroPlusRetrolens
Credit: Own work. Picture taken with: + (at 38 mm) + tripod.
Author: Christian Fischer
Usage Terms: Creative Commons Attribution-Share Alike 3.0
License: CC BY-SA 3.0
License Link: http://creativecommons.org/licenses/by-sa/3.0
Attribution Required?: Yes

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