As you dive into the world of photography, it will not take you long to notice that there is a lens for almost everything. For a beginner, a dilemma arises when you have to decide which lens to choose for certain photography subjects. Well, first of all, one must know that there isn’t a single lens that will do everything you need on a given subject. The working conditions won’t be the same every time and you’ll need to adapt and improvise. But, you can generalize certain aspects of the lenses available for different occasions.
This is a given – you will need a sharp lens, mid telephoto (35-135mm) with wide aperture. The reason you need wide aperture is to achieve selective focus and be able to utilize different light sources. Sharpness is crucial when it comes to portraiture since the images must be as clear as possible. Focal length, on the other hand, needs to be long enough to avoid distortion (like wide angle lens have) and short enough to avoid too much zoom compression. This is done due to the fact that the images must look flattering for the model, and to avoid distorting their look.
Wider lenses will do you good here, but you can’t limit yourself to one focal length. When it comes to landscape photography you have to take into consideration the distortion which wide angle lenses have, as well as the zoom compression. Zoom compression comes naturally with the focal length as well as the field of view and distortion. The longer the lens, the narrower the field of view. The distortion reduces and the zoom compression increases. Therefore, you’ll need to pick the right lens for the right scene, that is why you’ll need to cover 14-35mm at least.
When it comes to sports, choosing the right lens depends on the type of sports you are photographing. For example, if you’re shooting football (soccer in the US) the pitch is big, thus you’ll need long telephoto lens in order to capture the action. But long telephoto lenses require fast shutter speeds, therefore you’ll need long telephoto lens with wide aperture. However, if you’re shooting skateboarding, for example, then you as the photographer are quite close to the action, thus you need wide angle lens, fisheye even. Choosing the right lens for sports mostly depends on the location relative to the action, the light and your shooting style.
Photo by Ricky Aponte
Macro photography can be done in so many different ways. Ranging from improvising with magnifying glasses, to using microscopes to photograph stuff that aren’t even visible to the naked eye. But when it comes to lenses – considering you aren’t using other accessories to improvise macro – you need a lens that is able to do macro. That means you need a lens that is able to focus really close. Often these lenses are classified as macro lenses and have the word ‘macro' written on the body of the lens.
Different focal lengths produce different magnification ratios and different problems. Shorter lens means less magnification and easier shooting (less shake, can even be shot handheld), while longer lenses produce more magnification and are harder to wield handheld, thus you need a tripod for them. Macro is all about the detail, so the sharper the lens the better you’ll do. Stay away from zoom lenses with macro abilities. They might be good for learning, but they aren’t up to par with prime macro lens (even if the lens isn’t a macro lens and it is put on macro rings).
Photo by gidovd
If you are interested in the stars and the stars only, then you need a telescope with camera mount which is able to track the stars; sky that is clean and free of light pollution and you are set. However, if you were to shoot stars as part of a landscape shot, then picking the right lens is a different story altogether. Since the night sky is dark, you’ll need a lens with wide aperture (f/2.8 or wider) in order to gather as much light as possible. Focal length goes the same as in landscape photography, maybe a bit wider.
But the key thing for astrophoto landscapes is the coma. Coma is when the stars don’t appear as dots, but as streaks or crosses (not produced by star trails). In order to avoid coma, you need a lens which has aspherical element, which is the glass that corrects coma. Before buying a lens for astrophotography, do some research on it (some aspherical lenses still have coma). For the crop factor shooters out there, the Sigma 18-35 f/1.8 is great for this job. It is not that wide but that f-stop changes the game for crop sensors. The amount of light gathered is amazing, meaning more signal less noise and the coma is great.
Photo by Morloy
Lastly, there always will be deviations from the general rules of a thumb and that doesn’t mean you do it wrong. People shoot portraits with fisheye lenses and landscapes with 400-mm lenses. It doesn’t have to be strictly the lens that everybody is using.