Certified Professional Photographer (CPP) 2026 – 400 Free Practice Questions to Pass the Exam

The Sunny 16 rule offers a guideline for determining exposure settings on sunny days by suggesting that at f/16, the shutter speed should equal the ISO setting for a correct exposure. However, on a cloudy bright day, which provides softer light than direct sunlight, you need to account for the reduced brightness.

To adapt for this difference in lighting conditions, the aperture opens wider to allow more light in. Thus, shifting down to f/11 will give you a correct exposure while still maintaining a proper balance of light and depth of field. The shutter speed remains tied to the ISO in the same manner as the Sunny 16 rule, underscoring the importance of exposure relationship.

This understanding of how to modify settings based on light conditions is crucial for photographers to achieve optimal results in various environments, ensuring their images are neither overexposed nor underexposed.