The Kenko Auto Extension Tube Set for Nikon Cameras includes three extension tubes: 12mm, 20mm, and 36mm. You can use these tubes individually or combine them to achieve the magnification you're looking for. These extension tubes are a fantastic tool for macro photography as they allow your lens to focus closer than its normal minimum focusing distance. As you move the lens farther away from the sensor, the lens is forced to focus closer than it normally would. Getting closer has the effect of magnifying your subject so it appears larger in the viewfinder and in your photos. The greater the length of the extension tube, the closer the lens can focus. It's an inexpensive way to convert virtually any lens into a macro lens while maintaining optical quality.

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