FIGURE A2. Method of generating a mosaic image from several overlapping images and then marking and measuring linear features on the mosaic image. A region of TMM 40234-17 around that shown in Figure 5.1 is used as an example. 1, Three overlapping images. The same region is in better focus in some images than in others. 2, The three images aligned and overlapped. 3, The three images blended into a single image, with the best-focused image selected for each region.