I have this problem with different raster layers, in this instance it's land use data. In my layout, and in a rendered PDF of my map, the legend entry for the raster layer has an ugly, thick gray border around my raster color patches. Here's how they look when rendered to PDF:
Sometimes it's even worse, and ArcGIS appears to randomly choose a thick border for some colors and a thinner, lighter one for others, making my legend very ugly. Here's another example in a finished PDF:
Here's what the same legend looks like in the ArcGIS layout. The border width looks the same, nothing like the PDF. The color differences are not as pronounced as in the PDF but you can see they're there:
Is there any way to edit or remove those gray borders? I've searched a bit online and the most recent thread I've found is this one from the ArcGIS forums, with a couple workarounds that I may resort to, but I'm hoping for a simpler solution.
FYI, my rasters' symbology is set to use Unique Values, but using Colormap gives the same results.