Certified Professional Photographer (CPP) Practice Exam

What does adjusting the shutter's open duration control?

1. The color temperature

2. The depth of field

3. The amount of light

4. The grain of the image

The correct answer is: The amount of light

Adjusting the shutter's open duration directly influences the amount of light that reaches the camera's sensor or film. When the shutter is open for a longer duration, more light is allowed in, which can result in a brighter image. Conversely, if the shutter is open for a shorter duration, less light enters, leading to a darker image. This control over light exposure is critical for achieving the desired brightness and ensuring that details are captured appropriately, especially in varying lighting conditions. While the other options relate to different aspects of photography—such as color temperature affecting the overall color balance of the image, depth of field impacting the focus area in the frame, and grain relating to the texture of the image due to higher ISO settings—the duration for which the shutter remains open is specifically tied to the control of light.