Certified Professional Photographer (CPP) Practice Exam

Doubling the shutter open time results in how many stops of exposure?

1. One stop

2. Two stops

3. Three stops

4. Half a stop

The correct answer is: One stop

When you double the shutter open time, you are allowing twice the amount of light to reach the camera's sensor during that exposure. In photographic terms, this is referred to as increasing the exposure, which is measured in stops. Each full stop represents a doubling or halving of light. By doubling the duration the shutter is open, you effectively gain one full stop of exposure. This means that if you had a previous shutter speed exposure of 1/125 seconds and you change it to 1/60 seconds (which is indeed double the time), you have increased the light hitting the sensor by one stop. Understanding the relationship between shutter speed and exposure is crucial for photographers to manipulate light creatively and achieve the desired results in their images.