Question

Two concave mirrors have the same focal length but the aperture of one is larger than the other. Which mirror forms the sharper image and why?​

Answer 1

If two concave mirrors have the same focal length but the aperture of one is larger than the other then mirror which has small aperture leads to sharper image due to its small chromatic aberration and mirror which has large aperture leads to brighter image because of its large chromatic aberration.