4K and 8K systems are very promising media and offer highly realistic images. Such high-resolution video systems provide completely different impressions than HDTVs. However, it is difficult, even for a professional cameraman, to adjust the 4K/8K camera focus using only the small viewfinder on a camera. Indeed, it is sometimes difficult even to focus an HDTV camera with such a small viewfinder, and since 4K has four times higher resolution than HDTV, it is almost impossible to adjust a small viewfinder with the same size as that of an HDTV camera using only human eyes. Therefore, in content-creating fields, large monitors are generally used to adjust the focus; however, large monitors are bulky and do not fit practical requirements, which means that technical assistance is required. A possible solution to this problem is to detect the sharp edges created by high-frequency elements in fine-focus images and superimpose those edges on the image; the cameraman can then adjust the focus with additional information gained from maximizing the superimposed edges. However, conventional edge detection technologies are vulnerable against noise, which means that practical situations using this technique are limited to environments with good lighting conditions. This paper introduces a novel signal processing method that enables cameramen to adjust a 4k camera focus using their eyes.