One of my favorite features of the current version of SimRip is the new Print Preview function. When I designed this feature into SimRip, it seemed novel and interesting, but it has since become an important part of my halftone workflow. So much so, I think it deserves a post in the Blog, so here we go.
SimRip3 is designed to generate printable halftones. The high resolution output is suitable for making film. In addition, Simrip can be used to preview the halftone dots as they would appear on press, providing an opportunity to make adjustments to a color separation before committing the image to screens.
Dot Gain in the Halftones
The concept behind print preview is simple, apply dot gain to each channel, like we get on press, before converting them to halftones. The resulting file is not intended for making screens, but rather provides a preview of how the halftone dots will appear in print. The results can be printed to a calibrated color printer as a composite for a printed proof, or viewed on screen as a multi channel spot color document. Preview documents can be discarded without saving, after previewing.
The Print preview function has two options, The Gain setting determines the amount of gain that is applied to each channel. The Output option lets you set a lower resolution to speed up the process, since the output is not intended for screen printing, but rather for previewing. For previewing on screen and printing color composites an output setting of 300 provides good results. This means your resulting file will have a resolution of 300 ppi.
You can calibrate the gain setting by comparing the print preview output to the results you are seeing on press. Run a separation through SimRip using the standard options, make your screens and print the results. Now run the same separation through SimRip using Print Preview and compare the results either on screen or with a printed composite. Make adjustments to the Print preview settings until you get a value that matches your screen printed results.
The main benefit of running a separation through preview before making the conversion using SimRip is the ability to see the results of Dot Gain on press, before actually putting the separation on press. The preview can reveal Issues such as areas of low percentage dots, ink coverage in color transitions, total ink deposits on dark garments, and the effects of screen rotation on the halftones. By looking at a preview of your halftone print before making screens many issues can be addressed before your separations hit the press.