The subjective quality of images (human interpretation) is very important in long-range imaging systems, where the presence of haze directly influences visibility of the scene, by reducing contrast and obscuring objects. Image enhancement techniques - dehazing techniques, are usually required in such systems. This paper compares the most significant single image dehazing approaches, proposes three additional enhancement steps in dehazing algorithms, compares performance of the algorithms and additional enhancement steps, and presents test results on maritime surveillance images, which represent one special case of long-range images.