An ultrasound imaging system comprising: a scan converter configured to generate a three dimensional data set from ultrasound echoes received from a subject when imaging a volume of the subject; a volume renderer configured to calculate surface shading information of a first surface of the 3D data set based, at least in part, on a location of a simulated light source, and render a two dimensional projection image of the 3D data set which includes the shading information; and a user interface comprising: a display configured to display the 2D projection image; and an input device comprising a user interface element configured to receive first user input indicative of an in-plane position of the simulated light source within a projection plane of the 2D projection image, wherein the volume renderer is further configured, responsive to movement of the simulated light source via the user input, to automatically render the simulated light source at a location corresponding to the in-plane position and a depth position determined by the volume renderer, and wherein the depth position is set based at least in part on a quality criterion and at least in part on contours of the first surface such that a distance between the simulated light source and the first surface is maintained, wherein the quality criterion represents minimizing an amount of shadowing in a vicinity of the first surface of a ray of the simulated light source or maximizing a dynamic range of lighting intensity in the 2D projection image, wherein the depth position corresponds to a location along an axis normal to the projection plane at a set distance from the first surface of the 3D dataset, wherein the set distance is a constant distance from different positions on the first surface. a scan converter configured to generate a three dimensional data set from ultrasound echoes received from a subject when imaging a volume of the subject; a volume renderer configured to calculate surface shading information of a first surface of the 3D data set based, at least in part, on a location of a simulated light source, and render a two dimensional projection image of the 3D data set which includes the shading information; and a user interface comprising: a display configured to display the 2D projection image; and an input device comprising a user interface element configured to receive first user input indicative of an in-plane position of the simulated light source within a projection plane of the 2D projection image, wherein the volume renderer is further configured, responsive to movement of the simulated light source via the user input, to automatically render the simulated light source at a location corresponding to the in-plane position and a depth position determined by the volume renderer, and wherein the depth position is set based at least in part on a quality criterion and at least in part on contours of the first surface such that a distance between the simulated light source and the first surface is maintained, wherein the quality criterion represents minimizing an amount of shadowing in a vicinity of the first surface of a ray of the simulated light source or maximizing a dynamic range of lighting intensity in the 2D projection image, wherein the depth position corresponds to a location along an axis normal to the projection plane at a set distance from the first surface of the 3D dataset, wherein the set distance is a constant distance from different positions on the first surface. a display configured to display the 2D projection image; and an input device comprising a user interface element configured to receive first user input indicative of an in-plane position of the simulated light source within a projection plane of the 2D projection image, wherein the volume renderer is further configured, responsive to movement of the simulated light source via the user input, to automatically render the simulated light source at a location corresponding to the in-plane position and a depth position determined by the volume renderer, and wherein the depth position is set based at least in part on a quality criterion and at least in part on contours of the first surface such that a distance between the simulated light source and the first surface is maintained, wherein the quality criterion represents minimizing an amount of shadowing in a vicinity of the first surface of a ray of the simulated light source or maximizing a dynamic range of lighting intensity in the 2D projection image, wherein the depth position corresponds to a location along an axis normal to the projection plane at a set distance from the first surface of the 3D dataset, wherein the set distance is a constant distance from different positions on the first surface.