Certified Professional Photographer (CPP) Practice Exam

Increasing the exposure by one stop can be achieved by changing the shutter speed to what relative to the original speed?

1. Double the original speed

2. Half the original speed

3. Quadruple the original speed

4. Maintain the original speed

The correct answer is: Half the original speed

Increasing the exposure by one stop means allowing more light to reach the sensor. This can be accomplished by adjusting the shutter speed. To increase exposure by one stop, you need to allow light in for a longer duration, which is achieved by decreasing the shutter speed. If you change the shutter speed to half the original speed, you are effectively doubling the time the sensor is exposed to light, thus allowing more light to enter. For example, if the original shutter speed is 1/100 second, changing it to 1/50 second doubles the exposure time, allowing more light in and increasing the overall exposure by one stop. The other responses do not correctly depict this relationship. Doubling the original speed would mean making the shutter speed faster, which would reduce the exposure. Quadrupling the speed would also decrease the amount of light entering, and maintaining the original speed would neither increase nor decrease the exposure. Therefore, halving the original shutter speed is the accurate method to increase exposure by one stop.