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Macro Extension Tube Set

MaiKe digital three piece macro tube set. There is a 12mm, 20mm and 36mm extension tube which can be used with a lens singly or in combination.

An extension tube is simply a hollow cylinder that fits in between your camera and lens, causing the lens to move further from the sensor. This additional distance allows your lens to focus more closely, which in turn provides more magnification capability. Unlike most lens accessories, extension tubes don't add any extra optics, and are therefore relatively inexpensive.

An extension tube increases lens magnification by an amount equal to the extension distance divided by the lens focal length. For example, adding a 20 mm extension tube to a 50 mm lens will give a magnification gain of 0.4X. Therefore, if the lens's original magnification was 0.15X, then the new magnification will be 0.15X+0.4X=0.55X. The closest focusing distance will also decrease.