Chest X-rays are one of the most commonly performed procedures for diagnosing conditions affecting the chest and its contents. It's also represents the change of actual human body to compare the image produced by using different parameters. And comparing the image characteristics of a particular x-ray system with different techniques. The aim of this experiment is to obtain the best quality radiograph by evaluating the optimum parameters such as kVp, mA, exposure time, and distance associated with the film characteristic and to find the difference in optical density (OD) of air stepwedge with different thicknesses. The comparison of the image produced in terms of exposure assessment was made by using the Toshiba KXO 50R X-ray Machine. The RMI Radiographic Chest Phantom, Model 170B, was used as the subject matter in this experiment. Radiographic film KONICA MG-SR PLUS, which is green-sensitive film, was used and inserted into a cassette. It was placed right below the RMI Radiographic Chest Phantom, Model 170B and then was exposed by using different kVp, which were 60, 70, and 80 kVp with 2, 2.5, 3.2, and 4 mAs for each kVp. The source-to-image distance, which was 183 cm, was kept constant in this study. The film was then processed by using an automatic processor in the darkroom. From the observations, 80 kVp with 2 mAs provides a better image quality as compared to others, and the optical density (OD) of air stepwedge increases with increasing thickness.