Back to Dye Printing Tricks & Tips
Yes.
It keeps those nasty white spaces out from under your artwork. The simplest way to think about it is to consider how high speed printing is done. One color of ink is plopped down on the paper, then the paper moves to the next roller and more ink is plopped down. If the two adjoining plops vary as they go down, the paper shows through.
Poor trapping lets that sliver of white show
Trapping is adding just a little bit of overlap. Imagine a red circle on a green background. In the world of printing the green would go down except where the red will go.
You would want your circle's outline or stroke or line to overprint on top of the red. That way there would be enough leeway. We like to have a .25 point overprint. In PageMaker you can set a trap in the "Fill and Line" easily by tapping overprint on each object.
Adding a bit of trap (demonstrated here as the solid
red ring) puts overlap on top of the green
FreeHand and Illustrator have similar menus for setting up overprinting objects.
Should you overprint the entire red circle? Not unless you want a brownish circle. Remember the ring of trap is small enough to hide the problems of two colors butting up against one another. If you overprint a red circle on a full block of green, the two colors will mix together! It can be especially ugly if you make a drop shadow overprint your photographs...
Overprinting type is trickier. Depending on the color of the text and the background, utilities will let you set the over printing or do it within the print dialog. Black text can over print light colors easily. Other tints make for more homework.
The more you research the better your final job will appear.
When using process colors (CMYK) you can create a trap color manually. Mix a third color made up of the percentages of the other two adjoining colors.
CYAN |
MAGENTA |
YELLOW |
BLACK |
||
Adjacent Color #1 |
80% |
0% |
80% |
5% |
|
80% |
20% |
80% |
5% |
Trap Color | |
Adjacent Color #2 |
20% |
20% |
0% |
0% |