A common wish in non-destructive testing is to investigate a large object with a small interesting detail inside. Due to practical circumstances, the projections may sometimes be truncated. According to the theory on tomography, it is then impossible to reconstruct the object. However, sometimes it is possible to receive an approximate result. It turns out that the key-point is how to implement the ramp-filter. The quality of the result depends on the object itself. We show one good experiment on real data, linear cone-beam tomography for logs. We also show experiments on the Shepp-Logan phantom, well-known from medical CT, and discuss the varying reconstruction quality.
2002. 33-36 p.