1. A method for ensuring that a scanning process captures a high-quality montage image of a slide by enabling accurate focus control of image tiles of the slide, the method comprising the steps of: evaluating tissue regions of a thumbnail image and selecting several focus positions to initially focus microscope optics on a point-by-point basis; placing under the microscope optics each focus position, wherein the best-fit focus at each position is determined; generating a three-dimensional data set corresponding to an optimal specimen distance at each stage location, wherein data points in the data set are used as input to a routine that generates necessary control parameters for a slide scanning process; and passing the tissue information and control parameters to a component that is responsible for the motion of a stage and synchronization of a microscopic imaging system during a montage image acquisition.