Which method is effective in reducing image noise while maintaining usability?

Adding light is an effective method for reducing image noise while maintaining usability because noise is often a result of poor lighting conditions. In low-light situations, camera sensors struggle to capture clean images, leading to increased graininess and artifacts. By increasing the amount of light available, the camera can produce clearer images with more accurate colors and reduced noise levels. This is particularly important in settings such as security surveillance where clarity and detail are crucial for identifying subjects.

When the light levels are enhanced, the camera can operate at a lower ISO setting, which further limits the introduction of noise. Therefore, this approach significantly improves the overall quality of the image without compromising its usability for applications such as monitoring, analysis, or identification purposes.