Photon rate R in a slice through the z = 0-plane of the simulation box. First row: 32³ particles, Second row: 64³ particles, Third row: 128³. First column: t = 3.0 kyr, second column: t = 32 kyr, third column: t = 48 kyr, The black dashed circle represents the overdense clump. White solid circles represent the position of the sources. The black dashed lines delineate the shape of an ideal shadow behind the clump.