A digital proofer offers a faster method of internal product prediction than other devices. A digital proofer attached to the scanner can determine of images are scanned correctly, reducing rescans. If film from the imagesetter is used to determine how the press will print, the imagesetter is being used as a proofing device. This can be easily determined if the majority of the imagesetter's film output is rejected and redone. If sheets pulled from the press are used to determine the product, the press is the proofing device.

Substantial waste of materials and time can be prevented if a digital proofing device is used which produces the same output as the final step in the printing process, the press. The farther upstream in the production process the proofing device is placed, the greater the reduction in waste.

By sending a digitally produced proof along with a film-based proof which matches it, customers may be more inclined to accept digital proofs in the future. 

Author: Howie Fenton
Source: Newspapers and Technology, July, 1999, p. 31.
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