A thermal processor for thermally developing an image in an imaging material. The thermal processor includes an oven and a plurality of rollers positioned to form a transport path and, through contact with the imaging material, configured to move the imaging material through the oven along the transport path. Each roller has an initial contact point and a final contact point with the imaging material as the imaging material moves along the transport path. A spacing between the rollers is varied such that a distance between a final contact point and an initial contact point of at least a first pair of rollers along the transport path is different from a distance between a final contact point and an initial contact point of at least a second pair of consecutive rollers along the transport path.