Easily capture close-ups using an affordable alternative to dedicated macro optics
Many photographers are attracted to the idea of capturing revealing close-ups of flowers, insects and textured surfaces, but not everyone wants to invest in a dedicated macro lens.
Fortunately, there are a few alternatives to specialist optics and one of the most popular comes in the form of extension tubes. These vary in both price and length and are produced by the main camera manufacturers and third-party manufacturers alike.
Extension tubes are typically sold in sets, with 12mm, 20mm and 36mm being examples of typical sizes. The longer the extension tube, the greater the distance that is created between the lens and your camera’s sensor. It’s this relationship between the glass and the sensor that enables you to focus the lens more closely, producing a higher magnification than would otherwise be possible.
You can use an extension tube with absolutely any lens, but a standard lens of around 50mm up to a short telephoto lens works best. Zoom lenses, wide-angle lenses and indeed dedicated macro lenses can also be used with extension tubes, but you can encounter problems with wide-angles and zooms because the front element of the lens is extremely close to the subject.
There are two main types of extension tube: a cheaper, all-manual option and a costlier version that retains metering and autofocus capabilities, which gives greater control and accuracy.
When you unbox an extension tube, you’ll find that looks like a lens. However, there isn’t any glass. Some extension tubes feature electric contacts, enabling autofocus and metering to function.
You might find that the distance between the front element of the lens and the subject is quite small when using wide-angle or zoom lenses. Standard through to short telephoto focal lengths are ideal.
Extension tubes attach directly to the camera. The greater the tube’s length – and/or the greater the number of tubes you attach – increases how close you can focus.
Using a narrow aperture is a must. Even using f16 or f22, you will still find depth of field is limited. A higher ISO or the use of macro flash may be necessary to avoid a very slow shutter speed.
Even if you are able to avoid a slow shutter speed, it’s best to use a tripod when photographing macro subjects – no matter whether you are using a dedicated macro lens or extension tubes.
Shallow depth of field can make composition and framing challenging, so take your time and be ready to move the camera’s position forward or back slightly in order to refine the composition.