I’m working on a large illustration project in Illustrator CC. I hand-drew hundreds of shapes which overlapped to create the image how I wanted it to look. However, I have several shapes that needed to be cut out of ALL the shapes beneath it so that when I save as a PNG the cut-outs will be transparent. (These images will be placed on colored backgrounds in a digital setting). I used the pathfinder tool (Tried Trim and Divide, then used combine to build shapes that were all the same color) and now it seems that there are white lines as some screen artifacting or something? They are definitely not strokes, and when you zoom in and out their appearance changes. The first image shows what I’m seeing in Illustrator, but the problem seems to get worse when I save as PDF.
I’ve come across this problem before, but it’s always been print work. Since this is going to be used in digital, I need to find a fix for this so I can guarantee the image shows correctly. I found I can add strokes of the same color and they will disappear, but that is going to be extremely time-consuming for a project of this size. Does anyone have a fix for this or know a better way for me to create those cut-out transparencies so that I can avoid the problem all-together?
Answer
Another solution that is similar to adding a small stroke is to use Offset Path.
Select all objects and then select Object->Path->Offset Path. Set the Offset value to the same amount as you would stroke, this obviously depends on your situation so just use whatever works for you.
This way you don’t have to worry about the different colors, you just offset everything at the same time.
Note: Offset Path actually duplicates all the objects, so you end up with all the original shapes and the offset shapes above them. All the resulting offset objects are automatically selected after running Offset Path, so if you want you can quickly hit CMD+X to cut the selected offset objects, delete everything that remains, then CMD+SHIFT+V to paste the offset shapes back in place.
Attribution
Source : Link , Question Author : Micaela , Answer Author : Cai