Capturing around four to seven hours of real time freezing, each of these clips shows how ice crystals form on a very cold kitchen window. The time lapses were animated from around 55,000 photos in total, taken in Winnipeg, Canada by Brenda Loewen in 2016. After melting the overnight frost accumulation with a hairdryer, she would set up the camera and let the -15C to -25C (5F to -13F) degree temperatures reform the window frost:
Window frost (also called fern frost or ice flowers) forms when a glass pane is exposed to very cold air on the outside and warmer, moderately moist air on the inside. If the pane is not a good insulator (for example, if it is a single pane window), water vapour condenses on the glass forming frost patterns… The glass surface influences the shape of crystals, so imperfections, scratches, or dust can modify the way ice nucleates.
There are more videos about ice crystals on this site, including The Birth of a Snowflake, how to grow snowflakes in a bottle, and ice crystals form on the surfaces of backlit bubbles.