Rigid collodion is a solution of nitrocellulose in acetone, sometimes with the addition of alcohols. For makeup effects, it is used to create indented scars on the skin. When the acetone evaporates, it pulls and puckers the skin, creating very realistic-looking scars. Michael Davy Film & TV Makeup makes a tinted rigid collodion called Collodacolor that comes in translucent red, blue, and yellow.
Before applying rigid collodion (RC), make sure the skin is clean so the RC will stay on the skin without beginning to peel up at the edges.
If applied well, RC should stay on the skin for quite some time. After the skin has been cleaned with alcohol or astringent, apply a thin layer of either Top Guard® or Pros-Aide® to help the RC adhere to the skin better. Pros-Aide® might be preferable because of its flexibility when dry. After the RC has been applied over the adhesive where you want the scar to be, let it dry; the skin around it will pucker as the RC shrinks from the evaporation of the acetone. Then stipple a thin layer of Pros-Aide® over the RC to encapsulate it. Powder the adhesive to remove its stickiness. Powdering will also remove some of the shininess of the RC.
Stencils are a great way to add both accent and detail to a character or creature makeup. Stencils for all sorts of tattoos are available from Temptu and other sources, as well as stencils for creating shapes and patterns to mimic alien skin textures. Zazzo’s Character Troupe® templates designed by Brad Look are a great series of stencils that can be used for both beauty and alien character makeups.