Illustrator pathfinder trapping effect misbehavior

[mario16B8]

I can't use the trapping effect correctly
- the trap is wrong if the path have a stroke (it is created by the fill) see 1
- the trap is wrong if there is more than 1 fill color (it is created by the top fill) see 4
- the trap is wrong if fill is modified in the apparence panel, for example if you lower the opacity only of the fill, the trap remain full. see 4
- the trap doesn't work with images and gradients and despite the order of objects in the group is drawn on top of them (this is the worst thing)

am i doing something wrong?

[Monika Gause]

Did you try to use it from the Pathfinder panel?

Or did you group the objects before applying the pathfinder effect?

[Ton Frederiks]

You probably expect too much of Pathfinder Trap. It is meant for simple objects, not for images and gradients and strokes have to be outlined before they can be used with the effect. 

https://helpx.adobe.com/illustrator/using/trapping.html

[mario16B8]

Thanks for the reply
But it doesn't say in the documentation that it only works with simple and solid paths, also I understand that it doesn't work with images and gradients, but it could at least take this into account when create the traces and not creating them above

[Ton Frederiks]

It does mention on that page "The Trap option creates traps for simple objects".

To make sure that the Adobe engineers will look at your problems with trapping, please report them here:

https://illustrator.uservoice.com/

[Olivier273264736ctm]

It's strange, me everytime i try this tool it gives me this error message, even though i use very simple objects. Any idea on that?

[Ton Frederiks]

Are you working in a CMYK document?

[Olivier273264736ctm]

Yes i am.

[Ton Frederiks]

If resetting the trapping to defaults does not work, can you share an example .ai file?

CC filesharing, Dropbox, Google, WeTransfer...

[Ton Frederiks]

If all else fails, maybe consider reaching out to their support or user forums. 

By @App31521563b124

That is some very good advice!