A picture is worth a thousand words, but what the words are themselves are more so up to the designer/photographer, especially with context. Designers must include all of the components when either taking a photograph or inventing a unique illustrative image, but don’t assume that the photo will capture what’s needed to exist in…
In trapping cases involving smaller type, the eye can easily register changes in the shape of dark objects. To avoid type appearing over bold, shrink(choke) the background.
In a Spread, the above object gets “Knocked Out” of the object below it, & the above color is extended to cover the bottom color. In a Choke, the above abject gets “Knocked Out” of the object below it, & the background color is brought into the “Knocked Out” area to ensure proper trapping.
Sometimes the resulting color from the overprinting of 2 colors is a desired effect, as 2 inks overlap to create a 3rd color. Trapping would prevent the appearance of a 3rd color.
Through the printing process, paper can shift from 1 color unit to the next. Without any proper trapping, image shifting/misregistration will result.
Select a color for the stroke that’s a mixture of the 2 initial colors. Below for a Cyan letter on top of a Magenta background, we use a stroke that is made up of 40% C & 100% M—notice we use more of the darker valued ink.
Add a stroke to your object, then convert the stroke into a path: Object>Path>Outline Stroke—Outline Divide Fill the outlined stroke with a mix of 2 colors needing trapping. Use the pathfinder to subtract from the shape of your stroke.