Figure 5.

The absorbed-dose energy dependence of EBT and both lots of EBT2 as well as the mass energy absorption coefficient ratio of the active layers of both EBT2 lots to water. Also included is the absorbed-dose energy dependence at 50 keV for a hypothetical film, where the only film layer that is not water is the active layer of lot 020609 (only active) and a hypothetical film that is normal except that the active layer is made of water (no active). The uncertainties for only active and no active are smaller than the symbols.