Among photojournalists and street photographers, one hotly debated topic is lens selection. Ernst Haas (one of my three favorite photographers) said "the best zoom lens is your legs." This widely followed maxim employs a fixed focal length, wide angle lens combined with directions to move closer to "zoom in" and move away to "zoom out." The implication is that to stand in one spot and use the lens to zoom in or out is simply lazy.
It makes me cringe to disagree with the magnificent Mr. Haas but I think this approach misses a key point: the primary benefit of a zoom lens is to vary the angle of view to show more or less of the background, NOT to make the subject bigger or smaller.
To illustrate the point, imagine you're photographing a small boy pulling a wagon in front of a cathedral flanked by canals. As shown below, the boy and wagon are the same size in both frames but the backgrounds are quite different. On the left, the photographer has moved back and zoomed in so the narrow angle only captures the cathedral. On the right, the photographer has moved closer and zoomed out so the wide angle now captures much more of the background.
Angle of View
For most of my work, I'm constantly moving closer/farther, left/right and up/down so the image includes the things I want and excludes the things I don't want. The angle of view for my lens varies from 12 to 76 degrees so I'm also constantly zooming in and out to control the background behind my "star."
A good example is this week's photo from my Cuba series:
The guy in white was delivering eggs to a colonial mansion, [*] and as I really wanted to convey a "sense of place" I moved in close and zoomed out to include as much of the plaza as possible. If the plaza had been full of distractions -- electric wires, irrelevant signs, kids playing football -- I would have backed up, moved left or right, and zoomed in to exclude the clutter. (Unfortunately, I moved in too close and cut off his foot -- but that's a topic for another week.)
So, the next time you're at a public event, look for the photographer who is constantly moving their legs AND zooming in and out -- they're probably getting the best shots!
[*] Interesting side note -- a few seconds later this scene took an unexpected turn when the woman in the center with the white pail accosted the delivery guy in a futile attempt to buy some eggs (a scarce and strictly rationed commodity in Havana). He was polite but clearly determined that the buyer was receiving ALL of these eggs!