The first step to producing a sub-zero ambiance is to create mounds of soft, believable snow. Plan the base of your set according to what materials you normally use, and focus on embellishing the surface of your floor. Some animators use baking soda, piling it in deep drifts and sprinkling it over exterior surfaces. Others complain that this method is simply too messy and that the fine consistency of the baking soda is difficult to work with.
Wonderful effects can be achieved by the use of simple sugar or table salt. You can pile them around your set in much the same way as baking soda, but they are heavier and can be manipulated more easily. Salt is especially good to use because it has a bit of a sparkle to it, much like real snow. When sprayed with a fine mist, the outer layer can develop a thin crust, also emulating the characteristics of snow.
If you are working strictly with Claymation, you can achieve a very nice, old-time stop motion feel by the liberal use of cotton. Gather a large quantity of cotton balls and begin tearing and shaping away! Not only can it simulate a snowy groundcover or hilly background drifts, but it can creep and curl from a fireplace chimney and serve as steam that rises from your character’s mug of hot chocolate!
If your scene includes trees, make sure that they are stripped bare of any green foliage. You can paint the branches with a nail gloss or some clear casting resin in order to give them a slippery, icy sheen. This can also be used on any surface of your set that you would like to give a frosty look to.
Icicles can be created by simply using a glue gun and pressing out long streaks of glue. Experiment with different lengths, and set the pieces on a clean surface to dry. If you wish for your icicle to taper to a point, or if you simply want to create a bit of surface detail, you can practice manipulating the glue with a toothpick. Once cooled a bit, these icicles can be easily placed on your set or character and add to the wintry look of your scene.
If you wish to create snowflakes, you can use a bit of flour and a sifter. Slowly release a bit of snow for each frame you shoot. Polystyrene, or Styrofoam, can perfectly imitate the fickle movement of snowflakes. Shave flakes from a large piece of packing material, and carefully dispense them down onto your set. They will flutter and float and react to the slightest breeze, so they are ideal flakes to use if you would like to add a breeze or two to your flurries. Take a small sheet of paper and lightly wave it towards the flakes, and they will be swept in the direction you wish them to go.
The beauty of snow is that you can combine several of these methods in order to achieve different effects on the same set. If you would like to have tire tracks or wheel marks in your snow, you can layer baking soda across the front of your set and when you push a car through, it will retain those markings. If you wish to have glistening clumps of snow gathered alongside a street curb, you can use table salt and spray it with water. Larger, more voluminous hills which need to be in a background setting can be created on the cheap with piles and piles of inexpensive flour. However the combinations unfold, you are sure to create a magical winter wonderland!