Sample images (Stokes I, not deconvolved, natural weights) made using simulated data, covering about 10 × 10 square degrees in the sky. (a) Image before calibration. (b) Diffuse sky and the weak sources that are hidden in the simulated data. (c) Residual image after calibration, only using spectral regularization. (d) Residual image after calibration with spectral and spatial regularization. (e) Residual image after calibration with spectral and spatial regularization and using the diffuse sky model. Images (b)–(e) have the same intensity scale.