Why perform a regular calibration
To ensure that the output quality remains consistent and that the individual output devices produce comparable results, the HP Designjet 50PS printer must be calibrated at regular intervals (recommended: once a week), using the Close Loop Color Calibration function (automatic calibration). During calibration, a test pattern is sent to the proofer and in turn read by the proofer to generate correction curves.
note:A calibration cannot be carried out for some of the paper types and print qualities. For a more detailed explanation, refer to the HP Designjet 50PS EngineManager online help on the server.
Calibration procedure
During the calibration process, a page containing a test pattern is output on the printer. The ink is allowed to dry for a short time, and then the page is fed back into the printer and analyzed. For this analysis, the printer has been fitted with a densitometer which measures the color density. The resulting linearization curve is then used for uniform screening.
note:This curve is only used for density correction and not for color correction. For color correction, suitable profiles must be calculated using spectrophotometers and the appropriate programs.
This calibration is added to the system as a separate job. In other words, when the calibration process is started for the paper type selected, the job currently being printed is completed but the next job in the queue is paused until calibration is finished. This can take between five and seven minutes, since the ink must dry. The remaining job is then processed without any user inputs.
Starting a calibration
Calibration is started with a separate program, the HP Designjet 50PS EngineManager. It is automatically installed on the server during installation and can be launched by selecting Start, Programs, HPDesignjet 50ps, HP Designjet 50ps EngineManager. You can find more information in the online help for this program.
note:This program can only run if Java(TM) Runtime Environment 1.3 or greater is installed. This is automatically installed on the server during the installation of the HP Designjet 50PS software. You cannot launch this program from the clients.
