The smaller the cone angle, the lower these measurement errors. This means that it makes sense to design high precision machines with a greater distance between the X-ray source and the sensor. However, this reduces the efficiency of the X-ray tubes, because the usable part of the available beam cone is smaller. Depending on the desired accuracy, the machine manufacturer must find the optimal compromise.  Industrial X-ray tomography machines typically use area sensors with a scintillator.

Seen in image above:  Werth TomoScope® XL: Coordinate measuring machine with X-ray tomography for the most stringent requirements with a small cone beam angle (distance from focal point to sensor approx. 2.5 m); measurement range: length up to 800 mm, diameter up to 700 mm; length meas- urement error MPE E: (4.5+L/100) µm, L in mm.