Medical imaging data processing apparatus and method

A medical imaging data processing apparatus comprising a data receiving unit for receiving imaging data, a rendering unit for rendering images from the imaging data according to one or more rendering parameters and a selection unit configured to output a plurality of images rendered by the rendering unit. At least one of the plurality of output images is rendered using one or more rendering parameter having a value that is different to the value used to render one or more of the other rendered images. The output images are selectable to select the value of one or more rendering parameters associated with the selected image.