What are extension tubes and how are they used in macro and close up photography?
For those wanting to get in to macro photography an alternative to buying a specially designed, and often expensive macro lens, or using a close up filter is to use extension tubes. In their simplest form, extension tubes are little more than hollow plastic tubes, that contain no optics, that are placed between the camera body and the lens and by increasing the distance between the lens and the sensor effectively ‘forces’ the camera to focus closer to the subject. Almost any lens can be used with extension tubes, therefore only the tubes have to be purchased. Many modern DSLR lenses have auto focus mechanisms and allow the user to vary the aperture of the lens. Some extension tubes, such as those made by Kenko and Canon, have electrical elements that retain these features however there are some makes of extension tubes whereby these features are lost. The all singing, all dancing extension tubes that retain the auto focus feature, as well as varying the aperture are, as you’d expect th
