Certified Professional Photographer (CPP) Practice Exam

What happens to film exposure times longer than about a second?

1. Increase in grain visibility

2. Decrease in effective speed

3. Enhancement of color saturation

4. Improve dynamic range

The correct answer is: Decrease in effective speed

When film exposure times exceed approximately one second, the film's effective speed can decrease due to a variety of factors, including increased grain visibility and the likelihood of motion blur. When a longer exposure is taken, the film's response to light may become less efficient, leading to a decrease in the overall sensitivity of the film to light. This is particularly noticeable in slower films which may not handle extended exposures as effectively as faster films. Long exposures can also exaggerate graininess in the image since the same amount of light is allowed to hit the emulsion for a longer duration, leading to more pronounced grain issues. While longer exposures can enhance aspects like dynamic range and color saturation in certain circumstances, the primary concern with exposure times over one second is usually the decrease in effective speed, negatively impacting the film's ability to capture a sharp image without unwanted artifacts.