Trapping in Illustrator

[Lithografica]

In the unlikely case you want to apply trapping in illustrator, how would you deal with that?

Save your file as pdf and apply trapping in a pdf editor or are there other/better ways?

[oxburger]

Illustrator has a trapping option. I've never used it, but assume it would work o.k. (although I just did a test and it will only trap between solids and flat screen tints. It would not trap to a CT image or a vignett) Open up your pathfinder pallette, select "trap" and set your parameters.

see attached.

[pam_add]

best way a pdf editor , we are use a packedge from esko to create trap , including special cases (metalic - varnish - ...)
always there is special cases , don't forget this .
but in your case if you files all illustrator , is best to try esko trapx plugin it's great and demo is avalibe for 30 day i guess .

good luck

[mschilling]

The "best" way is to manually apply traps (overprints) to the objects as they are created. Then, if the objects are moved, etc., the traps will be retained, eliminating the need for retrapping the file. This usually is the best policy for files that may be reused and picked up again and again with only small changes. A close second is using Deskpack plugin for Illust which adds a layer with the overprints. The only disadvantage to this is that if anything is edited, the trap layer has to be considered.

[arkay_desai]

HI guys, I think illustrator having better options for trapping. set color and over print it. also you can see effects by selecting over print preview. Working with esco software is the end solution for all pre-press work.
some of examples in below sites, I hope it may helps you.
Overprinting Colors in Illustrator.
Real World Illustrator: Spot Colors, Transparency, and Overprints, Oh My!

[Thierry]

IMHO, the best way to apply trapping is to do it when ripping, when it is possible. This way, the trapping is only applied when needed and with correct values. But if you want to do it in Illustrator, it's quite possible.

The method explained in the link posted by arkay_desai works well and can also be used to overprinted thin stokes added to shapes. But there is also a more powerful function hidden in Effects>Pathfinder>Trapping (sorry if this path is not right but I only have a french version of Illustrator). First you have to group all the elements on which you want to apply the trapping. Then you go to Effects>Pathfinder>Trapping and you adjust the parameters according to your needs. The trapping is only made where it is necessary and the results is automatically modified if you move or transform an object (it's an effect and not a filter).

There is also another solution with InDesign. If you want, you may import the .ai file (it doesn't work with eps anymore) in an InDesign page and create a PDF using the print function (it's not possible with Export). This method is explained in an article posted on InDesignSecrets.com. It uses a powerful trapping engine inside InDesign. If you want to see the result, don't forget to activate the overprint preview in Acrobat. Otherwise, it can be ugly.