Extreme Macro Photography from Your Macro Lens
If you’re not super-serious about creating extreme macro photographs but you’d like to experiment with it, then increasing the abilities of your ordinary macro lens might be a good choice for you. Extension tubes and tele-converters are tools that can help turn ordinary lenses into macro and close-up lenses. Using these, you can turn an ordinary macro lens into an extreme macro lens.
A macro lens enables you to achieve focus close enough to a subject for a 1:1 magnification ratio. Adding an extension tube between your macro lens and your DSLR lets you get even closer. The larger the extension tube is (12mm, 25mm, 50mm, and so on) the closer you can get, and the more your subject is magnified.
The level of magnification you get from an extension tube varies depending on the size of the lens. For instance, a 25mm extension tube creates more magnification when paired with a 50mm macro lens than it does with a 100mm macro lens.
You can also use a tele-converter to increase the magnification of your macro lens. Tele-converters are optical devices that you place between the lens and the camera. Tele-converters magnify the image created by the lens before it reaches the digital sensor.
Tele-converters come in various levels of magnification (1.4x, 1.7x, 2x, and 3x). Unlike extension tubes, they create a consistent impact no matter what lens you’re using. A 2x tele-converter doubles the size of an image when paired with a 50mm macro lens or a 100mm macro lens (or any other lens).
If you take advantage of a macro lens’s ability to provide a 1:1 ratio (regardless of that lens’s particular focal length) while using a 2x tele-converter, your photograph will have a 2:1 ratio.
Because the tele-converter acts as a middleman (rather than simply creating space between the lens and the camera, like the extension tube does) it doesn’t cause you to move in closer to your subject. The magnification happens behind the lens rather than before it.
Tele-converters can lower the quality and sharpness of your images. Generally, the higher the level of magnification, the greater the loss in image quality.
Because they have optics of their own, be sure to seek a tele-converter that is high in quality and gets good reviews from other photographers online. Some forums and blogs post example images taken with various pieces of equipment. These provide a great resource for photographers who are shopping for new gear.