PHOTOOG Photography writings by Olivier Giroux

30Dec/080

Photography 101: Select Lenses to Results

The most widely-circulated advice in photography is almost certainly the tale of lenses and their purposes. Often it’s packaged (hidden?) in a complete dissertation on how to make postcard landscapes and other cookie-cutter photographs. There’s really no need for dogma in photography, you are free approach subject matter and perspective creatively.

Creative photographers, empowered with greater freedom, have been mixing up the rules until now there are more ways you can do things than not. Modern trends in photography encourage unusual combinations, such as landscapes taken with telephoto lenses and portraits with ultra-wide angle lenses. There is of course the risk of falling into a contrarian dogma too, so beware! The classics are still… well classic.

Before we proceed to tear them apart, let’s review the popular wisdom.

  • The Landscape

Mount a wide-angle lens (14-28mm) and hunt for a stream/rock/plant/person to place in the foreground of your majestic vista. Step down the lens to f/8-f/11, and then focus manually to keep both the subject in background and the foreground-filler object in focus (use the preview button to check). If you manage to keep the sky exposure from blowing out, you’ve got yourself a landscape.

  • The Portrait

Grab a short telephoto (60-120mm) with a moderately fast aperture (f/2.8 or faster). Shoot wide-open from 6-ish feet away for a headshot. If your subject is sitting under soft light (e.g. in shade or under a window) then you’ve got it in the bag. You can substitute a shorter lens if it is faster or a slower lens if is longer, as long as you adjust the distance accordingly.

One repugnant advice that is often offered to starting portraitists is to use the longest and heaviest telephoto lens they can carry/afford and play the role of a creep who photographs people unaware. I beg you don’t do that, it only diminishes photography by associating photographers with creeps. Instead let your subjects be aware of you, be patient and they’ll open up to you.

  • The Close-up

Use a powerful telephoto (200+mm) or a specially corrected (macro) lens together with a sturdy tripod. Step down your lens to stretch the razor-thin depth-of-field as needed. Let the tripod absorb the slow exposure, but try to stay far away from 1/4s (in either direction) if you’re not sure your tripod is up to snuff.

Close-ups are a relatively straightforward affair, and perhaps for this reason they are the subject of less controversy. I consider photography of birds and other wildlife to be a type of close-up photography where the lens of choice is a super-telephoto (400+mm) and the working distance is comparatively long.

Result-driven photography

Associations between genres and subjects aren’t set in law. The portrait genre can be applied to a variety of subjects, not just human beings. A portrait characteristically isolates a subject from other elements in the photograph (e.g. with shallow depth-of-focus) while the subject covers a large fraction of the frame itself.

The decision to isolate the subject with shallow depth-of-focus is what suggests the use of a moderately-fast short-telephoto lens: these lenses produce just the right combination of isolation and composition for a human portrait. Other options achieve the same effect of isolation by shallow depth-of-field. For example, a super-fast wide-angle lens used from a close range has similar effects but would include more of the surroundings around the subject. For another example, a slower but more powerful telephoto used from a distance isolates the subject both in depth and laterally.

The choice of isolating a subject or putting it into its context is more fundamental than the three archetypes above – the archetypes flow from this choice. Instead if you think in terms of subjects, isolation and context separately your options open up beyond the small set of classic rules.

Result-driven lens selection

Anything you see, tangible or intangible can be a subject. People, objects, colors, textures, light and shadow are all fine subjects. The scale of the subject and your freedom of movement play a crucial role in determining the range of focal lengths you can consider using. Large subjects at close range (comparatively) almost invariably demand a wide-angle lens, while small or faraway subjects often require a telephoto lens. Very often the range open to you is wide enough to open creative possibilities, which besides composition revolve around two concepts:

  • Isolating the subject from the background. You can achieve this effect in different ways that can be used in combination: (1) you can move closer, (2) you can open the lens aperture wider, or (3) you can use a longer lens. The classic portrait aims to create this effect by applying all three factors in moderation at once. The classic close-up usually creates this effect by accident, since both the first and the last factor are implied by the subject type.
  • Putting the subject into context with its environment. This is the domain of the wide-angle lens exclusively. You can combine this effect with the previous by working at close range with a wide aperture, but it is mutually-exclusive with the use of telephoto lenses (obviously). The classic landscape employs this effect.

You may not be able to achieve both effects together. If you do not have a wide-aperture wide-angle lens then it’ll be very difficult to combine the effects. Sometimes the subject dictates such a narrow range of focal lengths that it defines the effect of isolation and context for you.

The nifty fifty

No essay of mine on lens selection would be complete without discussing normal lenses. You’ll note a gap in the classic genres up above, where there doesn’t seem to be a use for lenses between 28mm and 60mm. Nonetheless the two most important lenses in the history of photography sit in this range: the 35mm and 50mm normal lenses, so-called because they are closest to the perspective of human vision.

These lenses are often very fast (f/1.4 and even faster exist) and sit at the crossroad between wide-angle (35mm) and telephoto (50mm) ranges. By moving the camera closer and farther from the subject, or opening and closing the aperture, these lenses can produce all of the basic creative effects in photography. They are by far the most flexible lenses and can be used by a skilled photographer to tackle virtually all subjects.

A parting note on the topic of zooms

I don’t like zooms, but most people do and that’s alright with me. This said, zooms often lead people down the road of un-creativity when they simply fit the frame to the subject without a thought about the effects of isolation and context. A zoom should be thought of as a “vari-focal” lens, which can give you the focal length you desire within a range. Ideally you should know what focal length you want to set the zoom lens to before you look through the viewfinder.


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