. The American journal of roentgenology, radium therapy and nuclear medicine . d in the diagram nostic value are its contrast and its defini- shown in Fig. i. The scattering material Any sign or detail in a radiograph is was a depth of 6 inches of water contained distinguishable by reason of its contrast in a tank 12 inches square; the bottom of with surrounding areas, just as any object the tank was of aluminum 1/32 inch thick. in nature is visible by reason of its contrast fThe influence of the preparation and positioningof the patient upon the diagnostic value of the radio-graph is a
. The American journal of roentgenology, radium therapy and nuclear medicine . d in the diagram nostic value are its contrast and its defini- shown in Fig. i. The scattering material Any sign or detail in a radiograph is was a depth of 6 inches of water contained distinguishable by reason of its contrast in a tank 12 inches square; the bottom of with surrounding areas, just as any object the tank was of aluminum 1/32 inch thick. in nature is visible by reason of its contrast fThe influence of the preparation and positioningof the patient upon the diagnostic value of the radio-graph is a medical question and is outside the scopeof the present investigation. Immersed in this was a block of beef bone3/8 inch thick and about I/2 inch square. Thetank rested on a lead sheet 1/16 inch thick,in which was a circular hole 3 inches in di-ameter. The film in a cassette or exposure Read at the Midwinter Meeting of the Eastern Section of The American Roentgen Society. Atlantic City, N. J., January 28, 29, 1921. 589 590 The Effects of Scattered X-Rays in Radiography. Fig. I. Diagram of experimental arrangement inexperiments on contrast. S, scattering material; B,small block of beef bone; D, lead diaphragm with3 inch aperture; F, photographic film ; L, sheet oflead. holder \ supported directly beneath thelead sheet and could be placed so as to re-ceive the exposure through the 3 inch aper-ture on any portion of the film; by thismeans six exposures could be obtained onone 8x10 film. The block of beef boneplaced in the center of the tank was in thepath of the central ray and its shadow fellon the film in the center of the circular aper-ture in the lead sheet. The first experiment was carried out todetermine the effect of undercutting ofscattered radiation. When an object em-bedded in scattering material is close to thefilm, it absorbs the diffuse rays as well asthe focal rays, thereby keeping the ratio oftheir intensities about the same. If the ob-ject is some distance
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