In this work, results for blind image restoration performed on the images of a target situated at a long range are given. The images are recorded by two cameras: one visible and one infrared camera. Visible and infrared images are dominantly degraded by the atmospheric factors (turbulence and aerosol) and the defocus aberration of the optical system, respectively. A curve is fitted to the edge spread function, using this curve the derivative and then the Fourier transform is obtained for determining the modulation transfer function (MTF). Later on, restoration is performed on the images using a Wiener filter constructed based on this MTF. Due to the curve-fitting performed on the edge spread function, noise which might occur when taking the derivative is prevented. To our knowledge, this work is the first one reported in the literature which performs image restoration using the proposed method on dominantly atmospherically blurred images.