Figure 3.

Images of the 3.2 mm steel rod using full and sparse aperture data. Reconstructions by SAFT using (a) full data, (c) 6.25% sparse data, and (e) 3.5% sparse data. Reconstructions by the SDUI method using (b) full data with ${\lambda }_1=500$, ${\lambda }_2=100$, (d) 6.25% sparse data with ${\lambda }_1=25$, ${\lambda }_2=5$, and (f) 3.5% sparse data with ${\lambda }_1=16$, ${\lambda }_2=3$. All dimensions are in millimeters.