Software compensation of chromatic-aberration effects on color photographs

A method is proposed for improving images formed by objectives with chromatic aberration. The focal length of an objective with this aberration depends on the wavelength, and therefore an image focused in one color range can be defocused and can have a different scale in another color range; this defocuses the picture and causes rainbow fringes to appear on the borders of objects. A description is given of how to correct such distortions by reducing images in the red, green, and blue color channels to the same scale and transferring the higher harmonics of the locally computed spatial Fourier spectrum from the more focused to the less focused channels. This also makes it possible to increase the depth of field of the picture. It is confirmed by experiments carried out in practice that the proposed method is effective. (C) 2020 Optical Society of America