Half of a lens is covered with black tape. What happens to the image the lens forms?

1. Light rays leave every part of the object and pass through every part of the lens, and all of them can build the final image. 2. Covering half the lens removes some of those rays but leaves rays from every object point still arriving. 3. So half a lens forms the same image, only fainter, because less light reaches it. 4. The common misconception is that the whole lens is needed to build the whole image, which the half lens result disproves. _Source: OpenStax College Physics (CC BY 4.0), Ch 25 "Geometric Optics", section 25.6 Image Formation by Lenses_