Now to render the glass. . . Still working in Photoshop, the first glass to be represented were filmy white and amber Opals and Opaks, and sparkling Seedy glasses. These glass types transmit AND reflect light, so are visible even when viewed from outside in daylight when transparent colors go dark – or from inside at night when other colors disappear. (Opals, Opaks & Seedies are explained in more detail at "Glass Types" under the "Resources" tab above).