First, we compare the results obtained from SD2Iu and the other methods using an experimental XRD-CT dataset acquired from a 3D printed SrNbO2N photocatalyst used for degradation of organic pollutants in water . The original sinograms of this dataset had 300 projections and 331 translation steps (the image size is then 331x331). The image reconstructed by CGLS with the full 300 projections is considered as the ground truth image when calculating the metrics shown in Table while the reconstructed images using the various methods are presented in Figure .