Marumi Kenko Auto Extension Tube Set

Extension tubes are designed to enable a lens to focus closer than its normal set minimum focusing distance. Getting closer has the effect of magnifying your subject They are exceptionally useful for macro photography, enabling you to convert almost any lens into a macro lens at a fraction of the cost while maintaining its original optical quality. However, you lose the ability to focus to infinity and the focus range is greatly limited to a very close focusing range.

Unfortunately I couldn't get my hand on the Kenko extension tube set, however instead I got a set from Marumi to test. The functionality probably is identical except Kenko comes with a set of 12, 20 and 36mm tubes compare to 13, 21 and 31mm tubes from Marumi. When stacked, they give a combine extension of 65mm. The extension tubes are made in Japan. The tubes are solidly made, mostly are metal. Notice the metallic contact circuitry on the tubes to maintain metering data and TTL auto exposure. I did try using the auto focus function, it kind of work only when you have the subject near focus anyway. Don’t expect it to find the focus automatically for you. Magnification test was done using Nikon 50mm f/1.4, which is a typical lens used with the extension tube set. The test subject is a 62mm Nikon cap.

No extension tube, minimum focusing distance with 50mm f/1.4	13mm extension tube
21mm extension tube	31mm extension tube
13+31mm extension tubes	21+31mm extension tubes
13+21+31mm extension tubes Notice the distortion near the edges