Ejected liquid forms a latent image on a charged transfer surface. In some invention aspects electrostatic charge is first applied to the surface; inkjet devices eject the image-forming liquid; voltage is established between the devices and surface; another, separate substance associated with the latent image actuates it. In other aspects hydrophobic or hydrophilic material in the surface stabilizes the image on it; electrostatic apparatus, associated with the surface, cooperates with the stabilizing material, further controlling image-droplet position and size. In other aspects a desired image forms on a final printing medium, based on an input electronic image-data array; the liquid ejection is onto an intermediate transfer surface, based on detailed incremental control by the data, forming a latent image representing the desired image. An actuating substance, initially discrete from the liquid, is associated with the image, and a reaction initiated to modify that substance—which is transferred from surface to final medium.