A plate-recording and printing system is provided with a printing plate recording
device for recording an image on a printing plate based upon binary image data
formed in an image data processing device, a printing press for carrying out a
printing operation by using the printing plate, an image pickup device for picking
up an image of a printed object and a profile forming device for forming profile
data of the printing press from picked up image data. A printing operation is carried
out under reference conditions by using predetermined ink and sheet of printing
paper. An image of a color chart on the printed object is picked up by the image
pickup. Print color of the color chart is determined in the Lab color system based
upon image data. Printing press profile data is generated as a function of print
color and predetermined reference color of the color chart. This profile data is
stored in association with kinds of ink and sheets of printing paper used in the
printing press. Prior to forming binary image data used in the printing plate recording
device, the image data processing device specifies printing conditions of the ink
and sheets of printing paper used in the printing press placed on the following
stage, and reads profile data related to these printing conditions. Then, it carries
out a color conversion on the image data by using the profile.