Certified Professional Photographer (CPP) Practice Exam

Which shutter speed would correspond to ISO 100 and f/16 exposure on a sunny day?

1. 1/50

2. 1/80

3. 1/100

4. 1/125

The correct answer is: 1/100

To determine the appropriate shutter speed for an exposure of ISO 100 and f/16 on a sunny day, we can apply the sunny 16 rule, which is a guideline for setting exposure based on the amount of light available on a clear, sunny day. According to the sunny 16 rule, when shooting outdoors in bright sunlight, you can set your aperture to f/16 and the shutter speed to the reciprocal of the ISO setting. At ISO 100, this means setting the shutter speed to 1/100 second to achieve a proper exposure. The reason this option aligns with the correct answer is that it follows the principles of exposure, maintaining a balance between ISO, aperture, and shutter speed in good lighting conditions. Using this rule, if you set your aperture to f/16, your ISO to 100 will indeed suggest a shutter speed of 1/100 to ensure that the exposure is balanced properly without over or underexposing the image. The other choices present various shutter speeds, but they either correspond to different scenarios or adjustments in exposure, such as letting in more light (slower speeds could result in overexposure) or fewer amounts of light (faster speeds could cause underexposure), thereby deviating from the ideal