At least two different printmasks are used for different printing devices--such as inkjet pens--that operate concurrently, or different printing steps that proceed concurrently, to produce respective image swaths in a single, pixel-based printing machine. In one form of the invention, the different printing devices produce different respective pixel-row pitches (related to resolution) on a printing medium, and the different printmasks help to minimize adverse patterning effects that result from interaction of the different pitches with dot-placement errors. The different pitches on the print medium may be provided through different pitches of marking devices (for example, the number of inkjet nozzles per unit distance along a pen) or in other ways. In another form of the invention the different printing devices are provided with different respective liquid-base colorants, to mark in different colors on a printing medium, and the different masks facilitate physical separation of the different colorants to promote drying. Earlier-applied colorants have more time to dry and penetrate before later adjacent or superposed application of other colorants improving print attributes such as bleed, offset, cockle, curl, overall drying time and throughput.