1. In a document processing system with a subsystem for generating electronic representations of respective images from a set of image data in accordance with a set of control instructions, the set of control instructions including a first subset of control instructions for controlling development of a first image, a second subset of control instructions for controlling development of a second image and a subset of image placemarking instructions, a method of developing a job for output with an output subsystem, comprising: (a) at a first time, generating a first electronic representation of the first image, with the generating subsystem, by reference to the first subset of control instructions; (b) at a second time, reading the subset of image placemarking instructions with the generating subsystem, wherein the second time is after the first time and wherein the placemarking instructions mark the location of an electronic representation of an image to be received by the document processing system at a future time; (c) at a third time, generating a second electronic representation of the second image, with the generating subsystem, by reference to the second subset of control instructions, wherein the second time is after the first time but before the third time; and (d) at a fourth time, electronically performing a selected function relative to a third electronic representation of a third image in response to said reading of (b), wherein the fourth time is at a future time after the first, second and third times and prior to the output of the job.