Certified Professional Photographer (CPP) Practice Exam

Which phenomenon occurs less in well-exposed areas of a digital image?

1. Color banding

2. Digital noise

3. Chromatic aberration

4. Lens flare

The correct answer is: Digital noise

Digital noise is a type of visual distortion characterized by the presence of random variations in brightness or color in an image, often appearing as graininess. In well-exposed areas of a digital image, the signal-to-noise ratio is generally higher, meaning that the actual image data dominates over the unwanted noise signals. This results in cleaner and clearer images, where noise is less noticeable. Conversely, poorly exposed areas, particularly in shadows or highlights, are more susceptible to noise. This can happen because the camera has to amplify the signal in these regions, which amplifies both the desired image and the noise, leading to a grainy appearance. In contrast, color banding typically occurs in areas of smooth gradients where there isn’t sufficient color depth to render seamless transitions between shades. Chromatic aberration emerges from lens limitations causing color fringes along high-contrast edges, and lens flare results from light scattering within the lens, particularly with strong light sources. These phenomena are not directly tied to exposure conditions in the same way that digital noise is, making noise the most relevant answer when considering how exposure affects visual quality in digital images.