Extension tubes a great way to focus much closer to small subjects such as an insect or flowers without the expense and weight of buying and carrying a macro lens. One extension tube takes up only as much room as a couple filters in a camera bag. Keep one or more in your camera bag at all times and you will always be ready for that macro shot.
The Kenko AF Extension Tube Set comes as a set of 3 tubes, a 12MM, 20MM and 36MM for Canon and Nikon DSLRS.
The Kenko AF Extension Tube Set for Micro 4/3rds or Sony E-mount Mirrorless cameras come as a set of 2 tubes, a 10mm and a 16mm.
They 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 (making it appear larger in the viewfinder and in your pictures). Extension tubes are exceptionally useful for macro photography, enabling you to instantly convert almost any lens into a macro lens at a fraction of the cost while maintaining its original optical quality.
The DG extension tubes have no optics. They are mounted in between the camera body and lens to create more distance between the lens and digital sensor or film plane. Moving the lens father away from the camera’s sensor forces it to focus much closer than normal. The greater the length of the extension tube, the closer the lens can focus.