There’s something rather thrilling about being able to examine something up close, and it can be anything, a common object or otherwise. If it’s in print form, so much the better, because when viewing prints—especially larger prints—you don’t have to squint through a viewfinder to see it. Regardless of whether you’re trying to photograph miniature subjects or simply garner the most sharpness out of life-size objects in a print, your best results will undoubtedly be realized if you use a macro lens. Unlike “close-focusing” optics or optics advertised as having macro focusing capabilities, true macro lenses are a class unto themselves by design.
Unlike their close-focusing, macro-capable, curved-field cousins, true macro lenses are designed to deliver optimal results with edge to edge, flat-field coverage of your subject. You might be able to get in real close with a close-focusing zoom or other lens with a macro feature, but the resolving power at close range is seldom—if ever—on a par with the resolving power of a true macro lens when racked out to its closest focusing distance. Depending on the manufacturer, macro lenses are also known as makro or micro lenses. By definition, true macro lenses focus down to life size (1:1), although a few macros only focus down to about half life size (1:2).
Ideally designed to capture edge-to-edge detail of flat artwork and documents, macro lenses are equally adept at capturing the finest details of three-dimensional objects, they’re available for all brands and formats of cameras and they come in a choice of focal ranges. Though most people think in terms of “normal” lenses (50-55mm) or short telephotos (100-105mm) when discussing macro lenses, these days macros are available in wide-angle and longer telephoto formats. Aside from the differences of fields of view between wide angle, normal and telephoto lenses, when using macro lenses there are other factors that determine whether you’re better off with one focal length over another.
If your goal is to illustrate a close-up of your subject in relation to its environment, a wider-angle lens is the obvious choice. But if photographing your subject from a distance of an inch or two away will spook your subject or cause it to flee (as in the case of butterflies and other skittish subjects) or cast unwanted shadows, a normal or longer telephoto macro lens is, by far, a better choice.
Case in point: when photographing subjects at 1:1 magnification ratios with a 60mm macro lens, the front of your lens is going to be approximately two inches from your subject. By comparison, photographing the same subject at 1:1 with a 105mm or 200mm macro lens allows for about six inches and ten inches of distance, respectively, between your camera and your subject. This greatly reduces the fright factor while simultaneously diminishing the chance of casting shadows on your subject when photographing with the sun over your shoulder.
Like all longer focal length lenses, telephoto macro lenses inherently make it easier to isolate your subject from the foreground and background visually, especially when shooting at wider apertures.
Something to keep in mind when choosing macros (or any type of lens, for that matter) is that a macro lens with a 1:1 reproduction ratio, designed for use on a full-frame 35mm camera, will still only focus down to 1:1 when used on an APS-C format DSLR. The image you see in your viewfinder will appear to be cropped tighter by about 50%, but the magnification ratio will always be the same 1:1 magnification ratio. So while your subject seemingly looks larger in your viewfinder, all you’re really viewing is a tighter crop of the image area as captured by your lens on the smaller sensor.