This article examines the benefits of color management and uses an actual job to demonstrate how color can be controlled.
Select a standard for proofing Selecting an input profile is an important first step. Prepress uses this profile to build the file. Pratt developed its standard by using a low-gain commercial MatchPrint made from 150-line/in. film at ReyHan PGF. You'll find that profile settings for input profiles do not matter and that UCR and GCR are not an issue because the purpose of an input profile is to convert builds to L*a*b*, not to create builds. Try to proof on something that approximates the color of your stock or on a material that is whiter.
Profile each output device on each substrate Pratt used linear film to print its color targets, but there is no reason why you can't apply a profile to curve-compensated film or direct-to-screen compensation curves. We simply find it easier to linearize every device. The important thing to remember is that you must be able to return your presses to this profiled condition. Use new squeegees, the same ink, the same screens, the same settings, and so on. If a screen press is profiled with worn squeegees, then the profile will work best with worn squeegees.
Print like you mean it Examine the printed color target for skipping or smearing before you allow it to become a profile. It's a good idea to include an image with faces and familiar imagery so the press operators see what ballpark they are in. The solid densities of the color target should be at or above the solid densities of the proof. If the proof has higher solid densities than the printed color target, then the press's gamut will be smaller than the gamut of the proof. Colors will get clipped, and banding may occur. An output profile can reduce color by converting solids to tones, but it cannot add color beyond a solid.
Program iQueue with the standard proof and output profile Pratt uses GretagMacbeth's iQueue to implement color-managed workflows. When a prepress operator drops a file in an iQueue hot folder, the software picks up the file, executes its programmed color-management routine, and then writes a new file on the server. The program will manage any number of queues. Pratt creates a queue for each substrate on each device at each line count. For example, we have profiles for a styrene substrate that we'll print on our M&R Conquest at both 55 and 85 lines/in.
Did you enjoy this article? Click here to subscribe to the magazine.