Fig. 5.
Measured count-rates using the 2.7D collimation and different cylinder sizes: (a) Trues, (b) Randoms, (c) Scattered, (d) NEC. Phantom size reduces the trues and NEC in a predictable manner. Randoms and scattered events tend to equalize for the different sized phantoms due to the competing effects of increased scattering and increased attenuation in the larger object.
