When shooting glass you might have problems with the light. Most commercial images of glassware is usually shot in a studio on a phototable. The images above are taken this way, with a light positioned on the floor below the table in a 45 degree angle towards the glass. Since the tabletop is made out of an opaque acrylicboard it lights up nicely. I used a 50mm lens with F1.8 aperture and low ISO. This photo required a some lengthy shutterspeeds so a tripod was essential. I filled the glass with water and put a few drops of ink in there and kept taking photos of it. The photo with three glasses is simply the same glass during different times. Hello Photoshop.
Read my blogpost on how to make your own DIY lightbox here.