Does it matter what side a laser user marks glass or acrylic that will be color-filled?

If you plan on paint-filling or color-filling engraved glass or acrylic, make sure you do not engrave on the reverse face. Because you will be viewing it from the front face, your eyes will have to look through the laser-marked graphics first, which are typically frosted, before they see the painted graphics. Hence, if you color-fill on the reverse face, you can expect a dull and milky appearance to your color.

   —Columbia Awards