How to Choose a Macro Lens
When you’re considering which fixed macro lens is best for you, the first thing to contemplate is which focal length works for your shooting style.
When it comes to macro and close-up photography, the longer a lens’s focal length (the higher the number in mm) the farther you are from a subject when shooting.
For instance, a 50mm macro lens and a 100mm macro lens may be capable of producing a life-size image of the subject on your digital sensor, but the 50mm macro lens achieves this at a closer distance to the subject than the 100mm macro lens. Each of these lenses has its own pros and cons, which I discuss in further detail in the upcoming sections.
Because the focal length of your macro lens affects your composition, your subject, and in some cases your light, you need to choose carefully. If you have multiple macro lenses in your camera bag, you have to decide which one will work best in a given scenario. If you’re considering purchasing your first macro lens, you have to determine which one will work best for the majority of the images you take.
Prioritize your needs. Consider these scenarios before you choose a lens:
If you are mostly concerned with the subject’s relationship to its background in your compositions, and you prefer to reveal as much of the background as possible then go with a wider macro lens such as a 50mm.
If you know that you’ll be photographing finicky subjects, go with the longest possible macro lens (which are generally more expensive).
In macro and close-up photography, issues with light are common. When using a wider macro lens (such as 45mm) you get so close to your subject that you’re likely — in the beginner stage, anyway — to cast a shadow over your scene. When relying solely on natural or available light, the farther you can be from your subject the less likely you are to run into this issue.
Most macro lenses serve multiple purposes. You can use them in close-up scenarios, but they also have the ability to focus to infinity. This means you can use them just like any other ordinary lens. So a 50mm macro lens can be used just like a 50mm lens.