Life in motion: freeze or blur? How to choose the decisive moment.

A photograph describes the present, which immediately becomes the past. It stops time in its tracks, taking an instant out of its context and either freezing it or blurring it to make a point and communicate an idea.

Photographers use this time option in various ways. They choose which moment to lift out of its context and capture as a photograph. They may select a fast shutter speed to stop action, or a slow one to blur it. Photographers such as Henri Cartier-Bresson have elevated the seizure of time into an art form by arranging the flow of shapes, forms and patterns within the frame to express meaning as a "decisive moment."

Here are four pictures that communicate, depending on how the photographer elected to use time to freeze, or time to blur.

Chicago free-lance photographer Jim Summaria captures the enthusiasm of a speaker by freezing his gesture and expression. The speaker's mouth forms a word, while his open hands underscore his point and tell us how strongly he feels about it. This photograph offers viewers insight into the speaker. Although they may not know him, or even care about his subject, viewers discern the passion this speaker brings to this moment in time.

In the second example, Summaria moves his camera to a basketball court to capture another kind of moment--one of maximum tension. Under ominous skies, a silhouetted player hangs in the air, a fraction of a second before he slams the ball through the hoop. Abstracting the scene through backlighting, Summaria makes sure that nothing will distract from this moment in time. He has stopped the flow of shapes within the frame to tell a story of skill, energy and athletic ability. He contrasts the body language of the player hanging in air with the figure of an earthbound player watching his flight. Summaria waits until the last possible instant to push the shutter button. The space between the hoop and ball becomes minimal, and the picture crackles with tension. Yet the player is still moving too fast for the camera to freeze entirely. His left hand becomes a secondary focal point--a blurred mass that tells us just how fast this is all happening.

During a visit to Russia last spring, I used choices in time to express meaning in two examples of my own travel photojournalism. In the provincial city of Yaroslavl, I photographed two whirling folk dancers at 1/30th of a second. They were spinning so fast that their dresses explode in a blur and their arms vanish altogether in the photograph. When I shot them at 1/15th of a second, their entire figures became abstracted to the point of invisibility. My photographic idea depends as much on how fast they are spinning as on my choice of shutter speed, I had to shoot more than 50 pictures of these dancers at various points in their routine and at various shutter speeds to get it right. Because I shoot digitally, I didn't have to stop to change film, nor did I have to worry about "wasting" pictures. Just kept shooting until I had captured the point I wanted to communicate--speed, energy and enthusiasm.

Rust hour in Moscow's vast Metro transit system is all about speed as well. Crowds of passengers wait along its platforms, as trains roar through its stations. To express the speed of these trains, I once again use a shutter speed of 1/30th of a second. Unlike the folk dancers who were awash in blur, this time I contrast the whoosh of a blurred train with the clarity of these patiently waiting commuters, This contrast creates an incongruity: these passengers won't go anywhere until this train stops for them, and it appears to be going too fast to stop. I choose this particular group of passengers because of the "x marks the spot" symbol created by the straps on the back of the woman in the middle of the picture. When will this train stop for her? That's the point of my picture.

Philip N. Douglis, ABC, directs The Douglis Visual Workshops, now in its 32nd year of training communicators in visual literacy. Douglis, an IABC Fellow, is the most widely known consultant on editorial photography for organizations. He offers a comprehensive six-person Communicating with Pictures workshop every May and October in Oak Creek Canyon, near Sedona, Ariz. For registration information, call +1 602.493.6709, or send an e-mail to [e-mail]. Send photos for possible use in this column to The Douglis Visual Workshops, 2505 E. Carol Avenue, Phoenix, AZ, USA 85028. You can view Douglis's new nine-gallery "cyberbook" on expressive travel photography at www.pbase.com/pnd1.