Macro photography is one of the most demanding disciplines of photography. The world of the small is a strange and unique place and makes some unusual demands on a photographer interested in capturing its beauty. Razor thin depth of field, extremely close working distances, and long exposure times combine to make macro photography a challenge. But it’s a challenge with a reward. Macros reveal a world that can’t be seen with the naked eye, alien landscapes, and strange creatures both beautiful and grotesque. I encourage you to try it. Many who do find a passion for macro photography they never knew existed.
Did you notice that I wrote macro and close-up photography in the title? What’s the difference, you ask? To get into that, we need to talk for a second about magnification. Every lens has some magnification factor usually expressed as a ratio (for example, 1:6). This ratio tells you what size the image of a real world object will be when projected by the lens onto your sensor or film. A ratio of 1:6 means that a 6 cm tall object will be projected at 1 cm onto the sensor. In other words, it will not be life size. A ratio of 1:1 means that a 6 cm tall object will be projected at 6cm onto the sensor—a life-size image.
True macro lenses have a magnification of 1:1 or higher. Most non-macro lenses have magnification ratios significantly less than that (1:4, 1:6, etc.). Why is the magnification important? Macro photography is all about photographing very small objects and you want that object to fill the sensor to reveal as much detail as possible. 35mm film and digital sensors provide a very small area. Filling that area with your subject will give you images with the maximum amount of detail.
Some manufacturers play a little fast and loose with the term “macro” and slap the designation on lenses that only have a magnification of 1:2 or 1:4. Now, 1:2 can provide really great images. But I’d call those close-ups rather than macros. Just remember, 1:1 is twice the magnification of 1:2—it gets you that much more detail and that much closer to your subject. If you get really serious about macro photography, check the published magnification ratios on lenses rather than relying on the macro designation.
In the end, does it matter what you call it? It does to some people. Here’s my take: 1:1 is going to get you the best macro shots possible but a great image is a great image and I don’t much care what you call it.
With all that technical mumbo-jumbo out of the way, what makes a great macro? Simple. The same things that make any photo great: composition, lighting, sharpness, etc. Just because you’re taking a photo of a bee doesn’t mean that the guidelines of composition no longer apply. You still have to think about subject placement in the frame, background elements, focus, depth of field, color, line, and form whether you are photographing ants or skyscrapers.
Probably the single most challenging aspect of macro photography is dealing with the depth of field. With such short working distances (often less than 20 inches), the depth of field becomes extremely narrow. We’re talking about millimeters here. And that makes focusing extremely difficult. The only way to increase it is to close down the aperture, but doing that increases the necessary exposure time. If you’re shooting stationary objects, the solution is to use a tripod. This will allow you to compose and focus precisely and gives you the ability to shoot with longer shutter speeds. If you’re shooting moving subjects (bugs, for example) a tripod won’t be of much use to you. You can either open the aperture to get suitable shutter speeds (realizing that will decrease your depth of field) or add some artificial light (a flash).
Because the depth of field is so shallow, you need to compose carefully to make sure that everything you want in focus is in the same plane. Either rearrange your subjects so that they are all the same distance from the lens or change your position to get the same effect. You can often focus more easily by just setting your focus on manual and moving your body closer or farther from the subject. Point and shoot compact cameras have an advantage over SLRs when shooting macros because they have an inherently larger depth of field. Using a compact, you will be able to use much larger apertures while retaining acceptable depth of field than you could with an SLR.
Another challenge is lighting and shutter speeds. Because of the small apertures you will probably need to provide some artificial light source to get your shutter speeds up. A flash can work well but at short working distances look out for the lens casting its shadow on your subject. It’s often better to use off-camera lighting, either off-camera flash or other lights.
Finally, you’re going to be dealing with subject movement. Movement that you wouldn’t even notice at normal magnifications becomes exaggerated in macros. The slightest breeze becomes a tornado and the tiniest shake an earthquake. Time your shots for when the wind dies down. Anticipate when whatever is causing the movement will stop and be prepared to make your photo at that moment.
Shooting macros can be tough. Technically demanding, they also require a high degree of patience and determination. Trying to get a decent macro of a skittish critter can literally take hours of hunting, anticipation, and careful movements. It can be physically strenuous. But when you capture something special, a view of a world that people don’t normally see, it makes it all worthwhile.