I sometimes need to subtract all of a certain color from a document, so that the background color shows through. (As in the surface the design is printed on) I know one way to do this is by using the pathfinder, and individually cutting out each shape - but this can sometimes be tedious. Is there a way to quickly select and cut out all of a color? I don't mean just deleting the color - because that still allows shapes underneath to show through. I hope this makes sense, I'm having a bit of trouble explaining.
Also, I'm currently using CS5
From the sound of things, Pathfinder is your best option.
You could always use Select > Same > Fill & Stroke and then set hte colors to none. But without seeing the artwork it's difficult to say of that would work for you.
I may not be explaining it clearly - This may be a better example, let's pretend I'm editing this shirt:
Lets assume that the bars continue behind the hand, and the hand is just overlapping them. If I wanted to delete the white fill of the hand, and instead have the shirt color show through, is there a more simple way to do this then by using the pathfinder? If I use Select -> Same -> Fill & Stroke and then set the color to none, the bars behind the hang will still be visible. This shirt is not my art, I'm just using it as an example.
Create a global color called shirt Color , then chaneg the white hand fill to the colro you created. When you print seperations, just dont print the the shirt color channel.
Since this is a global color you can then quickly explore other shirt colors.
Another way that can achieve this is to select all white objects and set their fill to 0% opacity. Then group everything and in the Transparency panel click the Knockout Group box until a checkmark appears. This method is not destructive to the shapes of the objects and can be used for more flexibility while developing the artwork if the destination requires rasterizing in the file. I would use Scott's method for delivering final artwork to client or for output that requires this kind of path topology.