Astronomical plates have a very large density range (dynamical range). Many exposed astronomical photographic plates do not provide detailed structures for very high densities, and some include hidden images for very low densities. The former can be fixed through 'Unsharp Masking' technique and the latter through 'Image Amplification' technique. Besides, we can find intrinsic colors of celestial bodies through 'Tri Color Composition' technique. Images of several plates which were observed from Sobaek Observatory with 61cm telescope are reproduced by the three kinds of image reproducing techniques. As reproduced image examples, we display an Orion nebula and a waxing crescent moon images through unsharp masking technique and an M81 image through image amplification technique. An Orion nebula and a Dumbbell nebula images are also given as results of tri color composition technique.

1) 앞서언급한 3가지 QC 의 요건으로 분류 될수있다 (환자， 기기， Filming) 2) 위 3 요소중 가장 저급한 한곳에 의해 전체 QC 의 결과가 좌우되므로 전과정 모두에 정도관리의 노력을 기울여야 할것이다. (Patient preparation-Coil application-Proper software control and option selections-State of art filiming and processing) 3) 매일의 Quality저하를 간과할수있다. 그러므로 ， 필요에 따라 수주전 혹은 1 년전의 화상(젠 1m) 과 비교해볼 필요가 있다.