Play with patt erns
Here’s another fun way to play with refraction. Simply make a black-and-white lined pattern in Photoshop then print it out; any office inkjet printer and plain paper is fine. Place the pattern in the background with glasses in front, making sure they’re as clean as possible. Fill them with different levels of water and experiment with the distance from the pattern to fine-tune the effect. If you want a reflective base like this, try using a sheet of glass with a piece of dark material underneath.