Certified Professional Photographer (CPP) Practice Exam 2025 - Free CPP Practice Questions and Study Guide

Fast shutter speeds are primarily used to capture movement. When photographing subjects that are in motion, such as athletes or vehicles, a fast shutter speed is essential to freeze the action and prevent motion blur. This allows the photographer to capture crisp, clear images of moving subjects, making it possible to highlight details that would otherwise be lost if a slower shutter speed were used.

In contrast, enhancing color saturation, increasing exposure time, and softening depth of field are related to different aspects of photography. Color saturation is influenced by lighting conditions, post-processing, and the use of filters, rather than shutter speed. Increasing exposure time refers to using longer shutter speeds to allow more light to hit the sensor, which is the opposite of using fast shutter speeds. Softening depth of field pertains to aperture settings rather than shutter speed; wider apertures create a shallower depth of field, affecting how much of the scene is in focus. Thus, the primary function of fast shutter speeds is effectively utilized in capturing movement.