The NIST phantom was acquired with a 3D RF Spoiled Gradient Echo sequence (TR = 18 ms, TE = 6 ms, FA = 10 degree). Because T1 and T2 of the water filled with the container were 4000 ms and 2000 ms (too long for simulation!), a large number of subvoxels were required to describe multiple echo effects along the readout direction of the voxel. The actual calculation was performed for 2D sections using 256 x 1 x 1 (readout, 1st encoding, 2nd encoding) subvoxels and finally synthesized to obtain the 3D image (256 x 256 x 256 matrix). The total calculation time was about 73 min.

The following cross-sections show horizontal (coronal) planes for the fiducial spheres, proton density standard spheres, T2 standard spheres, and T1 standard spheres.