A color key consists of layers of clear media, where each transparent layer represents only one color separation. For example, a color key could consist of four layers of clear media, one for each of cyan, magenta, yellow, and black. Color keys are sometimes called overlays. For Matchprint Inkjet proofers, the color keys feature requires clear media, 1-bit TIFF input files without master files, and a specific hot folder setup.
Color keys require Epson Stylus Pro printers to use 1440 x 720 resolution. If you choose to calibrate the clear media, use three sheets of blank Paper Type 1 media of the same size and type as measurement backing.
Give clear media extra drying time to avoid damaging the proof or smudging the ink. It is recommended that you wait 30 minutes or longer for the ink to dry. Be particularly careful with heavy ink areas, such as dark blue and black. Ensure that the ink is dry before allowing the color keys to fall into the finished proof catcher. You can use the Media Configuration Editor to shorten or lengthen the Drying Time Per Page option to specify how long the proofer should wait for the ink to dry before cutting the proof. Even more drying time may be required before you can stack the color keys on top of each other, without having the layers of clear media stick to each other.
A special hot folder setup is also required to print color keys: the hot folder accepts only 1-bit TIFF files without a master file (.ini file). When you submit 1-bit TIFF files with a master file, the job fails.
Note:
For Matchprint Inkjet proofers, you cannot use the Certified Process for Color Confirmation when printing color keys.
| Parent topic: Using halftone input files |