1. A method of digitally printing a security feature with a single colorant, comprising: optically scanning, at a lower resolution, a medium having a security background preprinted thereon at a higher resolution, the background having a first region with a first preprinted pattern and an abutting second region with a different second preprinted pattern, the first and second regions substantially indistinguishable to the naked eye, the scanning producing a security image; analyzing the security image to identify a first pixel pattern of first binary pixels corresponding to the first region and a second pixel pattern of second binary pixels corresponding to the second region; printing the first and second pixel patterns with the single colorant; determining a darker one of the first and second printed patterns; and printing the security image at the lower resolution with the single colorant, the region corresponding to the darker printed pattern printed at a reduced gray level such that the printed first and second regions are substantially indistinguishable to the naked eye.