Among other things, one or more techniques and/or systems for generating a three-dimensional combined image is provided. A three-dimensional test image of a test item is combined with a three-dimensional article image of an article that is undergoing a radiation examination to generate the three-dimensional combined image. A first selection region of the three-dimensional article image is selected. The three-dimensional test image of the test item is inserted within the first selection region. Although the test item is not actually comprised within the article under examination, the three-dimensional combined image is intended to cause the test item to appear to be comprised within the article.