Certified Professional Photographer (CPP) Practice Exam

What photographic technique is used when tilting a camera up to capture a tall building, causing an effect of convergence?

1. Perspective shift

2. Keystone effect

3. Depth of field

4. High dynamic range

The correct answer is: Keystone effect

The technique being described involves tilting the camera upwards to capture a tall structure, which results in what is known as the keystone effect. This phenomenon occurs because the camera lens captures the upper part of the building at a wider angle compared to the lower part. As a result, the vertical lines of the building appear to converge toward the top, creating a visual distortion that resembles a keystone. Understanding the keystone effect is important for photographers, especially when photographing architecture or tall structures, as it impacts the composition and overall aesthetic of the image. This technique highlights the relationship between the camera angle and the perception of vertical lines within the frame, emphasizing the need to consider perspective when capturing such subjects. Perspective shift, while related to changes in viewpoint and composition, does not specifically refer to the convergence of vertical lines in this context. Depth of field involves the sharpness range in an image and does not relate to the angle of the camera in relation to tall structures, and high dynamic range refers to a technique that captures a wider range of luminosity but also does not pertain to the convergence effect seen when tilting the camera.