Raster proofers take the already processed and imposed raster data, as it will be imaged on the imagesetter/CTP, simulating the in-rip imposition, halftone dots etc. on the proof.
Advantages
- Guaranteed data integrity: content differences between the proof and the print are impossible.
- Halftone simulation: the look of the proof will be more authentic; it also might help in detecting moirés.
- Imposition simulation: the user has the ability to simulate the imposition made in StudioRIP.
- Ease of use: using the already ripped files, proofs can be created with one mouse-click.
- Fast: the job does not have to be processed twice.
Disadvantages
- Reduced colour accuracy: the typical colour accuracy is about average ∆E = 2.5 (whereas contone proofing can achieve average ∆E < 1),
- Non-CMYK problems: the colour accuracy is lower for non-CMYK colors.
- Several profiles needed: the profiling work needs to be done for each simulated ICC, as well as for every utilised used line screen, calibration curve, etc.
