We can use this mask, overlaid with the two images, to select the sharper flower from the f32 exposure (using the white part of the mask) and the softer background of the f/11 exposure (using the black part of the mask). For the result, click Next. Notice that the mask is blurred slightly at its edges to provide a smoother transition between the two parts being combined. We could even use a contrast mask (256 levels of tone from black to white) in order to achieve more subtle selections of portions of each image. The contrast mask could be used to combine two images taken to expand the camera's dynamic range to capture a scene with very bright and very dark areas(that the camera could not capture in a single exposure - sunrise; white cat in a coal mine; sunlit snow and deep shadows).