An image sensor includes first and second pluralities of photodiodes interspersed among each other in a semiconductor substrate. Incident light is to be directed through a surface of the semiconductor substrate into the first and second pluralities of photodiodes. The first plurality of photodiodes has greater sensitivity to the incident light than the second plurality of photodiodes. A metal film layer is disposed over the surface of the semiconductor substrate over the second plurality of photodiodes and not over the first plurality of photodiodes. A metal grid is disposed over the surface of the semiconductor substrate, and includes a first plurality of openings through which the incident light is directed into the first plurality of photodiodes. The metal grid further includes a second plurality of openings through which the incident light is directed through the metal film layer into the second plurality of photodiodes.