Photography News Issue 44

Photography News | Issue 44 | absolutephoto.com

Technique 20

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Changing lenses alters the way you see the world, and at no time is this truer than when using macro models. Telephoto lenses can magnify distant subjects and wide-angle models pack in more of the scene, but macro lenses reveal things you often can’t even see with the naked eye. It could be the minute textures of a flower petal or the intricate details of a tiny insect; it could be the internal workings of a watch or the workmanship of antique jewellery or toys. Start wielding a macro lens and you’ll find there are amazing subjects everywhere. Because of their longer focal lengths and fast maximum apertures, macro lenses can also make very usable portrait lenses, so you're getting two great tools for the price of one. A macro lens is designed to focus much closer than a normal lens can – sometimes mere centimetres from the front element. This leads to lots of magnification, the more of which there is, the more of the frame will be filled by the subject. With true macro lenses, the subject can be reproduced at its actual size on the sensor. This is called a 1:1 life-size reproduction or 1x magnification. So, if you were shooting a penny, which measures 20.3mm, at a 1:1 reproduction ratio, it would be focused on the sensor at the same 20.3mm size. This of course leads those amazing details. This power needs to be handled with care though; with such a huge magnification, focusing must be precise, and even tiny movements from the camera or subject canwreck the crisp details. Wide apertures give very little depth-of-field and lighting can be tricky with the camera lens so close to the subject. Combine the right lens, solid technique and some artistic endeavour though, and you’ll have the recipe for outstanding pictures. Up close With its amazing power to magnify the tiniest subjects, a macro lens is your ticket to a voyage of photographic discovery. But these powerful tools must be used with care for best results. Here you’ll find out how Words Kingsley Singleton Pictures Will Cheung and Kingsley Singleton

You might already have a telephoto lens with a ‘macro’ setting, or a compact camera with a macro mode, so why would you need a dedicated macro lens? Aside from the greater image quality you’ll find by choosing a lens that’s designed purely for macro work, the big divider is the level of magnification you can achieve. Only true macro lenses can achieve a 1:1 reproduction ratio (or a 1x magnification), where the subject is rendered at its actual size on the sensor. While many telephotos, such as the Sigma 70-300mm f/4-5.6APO DG Macro have a macro setting, it’s often 1:2 (0.5x) or 1:3. That’s good enough to be considered ‘close up’, but not true macro. Minimum focusing distance and minimumworking distance The level of magnification you can achieve depends on how close you can focus, and all lenses will state a minimum focusing distance. This is measured from the sensor (also referred to as the film plane or focal plane) to the subject, rather than the front of the lens. You can see where the focal plane sits as it’s marked on the camera as a circle with a line through the middle. The minimum working distance is the distance from the lens's front element to the subject. This is a really important figure and gives you an idea of how close you can get.

A very short working distance is fine for many subjects, usually florals and still life. But having the camera close to the subject does make lighting them more difficult (you may block the light and leave it in shadow), and live subjects may get scared off by your presence. For the latter, a longer working distance is more useful. Which focal length do I need? Macro lenses with longer focal lengths tend to provide more working distance and so something like a 150mm or 180mm lens with a minimum focus of 40-50cm is useful for nature. But there are also the general principles of focal length to consider. For example, a longer focal length will seem to affect the perspective, compressing foreground and background elements and giving a tighter look to the frame. However, macro lenses with longer focal lengths will also be more liable to camera shake. Conversely, wider macro lenses, like a 50mm, will have a shorter working distance, and while that’s not so useful for certain subjects, it does mean you can frame up closer and use the wider field of view to your advantage. For example you can show more of the subject’s environment or interesting textures. Of course, if you’re shooting with a smaller than full-frame sensor, your view will be cropped by a

Pick the right lens

PART 1

Everything you need to know about choosing a macro lens

Above These two images of the same flower show the potential of amacro lens. One was shot on a regular 50mm lens at the closest focusing distance of 40cm; the other is froma Sigma 50mm f/2.8 EX DGMacro, wherein the 13.5cmminimum focus produces a huge enlargement and lots of detail.