Autofocus in a camera operates by using a sensor to detect the contrast and sharpness of objects within the camera's frame. The sensor will then calculate the distance to the object and adjust the lens accordingly to achieve the sharpest focus possible. This process is typically done using one of several autofocus methods, such as phase detection or contrast detection. Phase detection autofocus is commonly used in DSLR cameras and works by splitting incoming light into pairs of images that are compared to determine focus. Contrast detection autofocus, on the other hand, analyzes the contrast in the image to find the point of highest sharpness.
Additionally, some cameras also utilize advanced autofocus technologies, such as hybrid autofocus systems that combine phase and contrast detection for quicker and more accurate focus. Continuous autofocus is another feature that allows the camera to continuously adjust focus as the subject moves, ensuring sharp images in fast-paced scenarios. Overall, autofocus in a camera is a complex system that relies on advanced technology to deliver precise and consistent focusing results in various shooting conditions.