An image intensifier based computed tomography scanner and a tube source of X-rays are used to obtain the images of small objects, plastics, wood and soft materials in order to know the interior properties of the material. A new method is developed to estimate the dgree of monochromacy, total soild angle, efficiency and geometrical effects of the measuring system and the way to produce monoenergetic radiation. The flux emitted by the X-ray tube is filtered using the appropriate filters at the chosen optimum energy and reasonable monochromacy is achieved and the images are acceptably distinct. Much attention has been focused on the imaging of small objects of weakly attenuating materials at optimum value. At optimum value it is possible to calculate the three dimensional representation of inner and outer surfaces of the object. The image contrast between soft materials could be significantly enhanced by optimal selection of the energy of the X-rays by Monte Carlo methods. The imaging system is compact, reasonably economic, has a good contrast resolution, simple operation and routine availability and explore the use of optimizing tomography for various applications. Keywords: Plastic, materials, image intensifier, optimum energy, monochromacy, soft materials, profile, Monte Carlo methods.