Details:
Summary:
This is an intermediate report of work-in-progress concerning technical issues relating to the effects of relative humidity in the growing field of digital printing. From this pretest stage of research we identify variables and technical problems with digital printing that may be related to relative humidity. We subjected a variety of desktop office printing devices to the test of printing a standardized file to study how they perform under normal atmospheric conditions. Substrate was standardized. Ambient temperature and relative humidity was controlled. Printed dots of varying sizes are scanned using a digital microscope and images were captured for evaluation. ImageJ software is used to measure dot areas that are graphed and compared for variations to a reference dot. Surface plots are generated and evaluation shows variations between different printing devices. A scanned solid block was imported into ImageJ and a line of standardized length was drawn from a solid block across a white unprinted area. Plot profiles generated in ImageJ was used to evaluate the differing changes in line shape between the images from the different devices. First deviations were calculated and graphed to show the rate of change of pixels as the line crosses over the solid edge. The printer requiring the least number of pixels was determined to most closely represent the reference edge.