The image plane is an imaginary flat surface inside a camera where a sharp image is formed after light passes through the lens. It is positioned at right angles to the optical axis and is where the camera's sensor or film sits to record the image.
The distance between the lens and the image plane changes depending on the focus distance-when a subject is closer to the camera, the lens must move further from the image plane to maintain sharp focus. Understanding the image plane helps photographers grasp key concepts such as focus, depth of field, and lens behaviour, leading to more precise and controlled image capture.