In order to achieve a successful mammographic image, this mammogram must contain sufficient diagnostic information to be able to detect any pathologic condition, using as low as reasonably achievable dose (ALARA). Therefore the Quality Control (QC) applied to the mammography machine must ascertain that the equipment performs at a constant high level of quality. Quality Control determines the tests necessary to uncover defects, and establish tolerance levels for adequate performance of equipment. The purpose of this study is to describe the influence of the acquisition parameters and the different acquisition modes on digital image quality, and explain the quality control tests applied on the BMI mammography machine. The relation between the acquisition parameters and the digital image “Contrast, SDNR and Score” is identified. The effect of filtration and the AEC photocell detectors on image quality is developed too.