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MACROPHOTOGRAPHY TOOLS, TIPS & TECHNIQUES FOR DIGITAL PHOTOGRAPHERS 2012
Extension Tubes
On the left is an Olympus variable length extension tube, and on the right a set of three Kenko auto
extension tubes.
Another way you can move your camera closer to your subject is to place an extension tube between
your camera and lens. Extension tubes are hollow and do not contain any glass elements; therefore,
they do not degrade the image produced by your primary lens. The amount of magnification you can
achieve will depend on the amount of extension and the focal length of the lens you use them with.
Longer focal length lenses require more extension to achieve the same amount of magnification.
Extension tubes come in fixed lengths (e.g., 7, 15, and 25 mm are common sizes). You can combine two
or more tubes for greater extension. Generally, the greater the extension the greater the magnification
achieved. Olympus makes an auto extension tube that varies in length like a set of bellows, and it is
great for working in the field. Extension tubes reduce the amount of light entering the lens but result in
no appreciable loss of sharpness. In this respect, extension tubes are superior to closeup filters.
Another advantage extension tubes entail is that they can be used with any lens you own to make it
focus more closely including your telephoto lenses. A set of three extension tubes costs about $200
new, $100 to $150 used. Because they contain no glass elements, brand names are not important, so
long as they fit on your camera and permit the metering system to work. Auto extension tubes are
preferred – these allow you to view your image with the aperture wide open. I recommend testing them
in the store with your lens before you buy a set. You can also buy just a single tube. The great thing is
you can attach them to a wide angle lens, normal lens, macro lens and even a telephoto lens, and they
will permit your lens to focus more closely. They are a great way to get started in macrophotography.
Robert Berdan | 16