What a pain to be on a crime scene at 2 a.m. and have to mix ingredients together to cast a tool impression on a doorjamb! It's hardly worth the mess so instead of casting it you just photograph it. Try the Extruder gun instead. It acts like a caulking gun. Simply insert a double cartridge into the gun, put on a special mixing tube and then squeeze the trigger. The compound will come out through the mixing tube that is laced with veins to mix the two compounds. When it comes out, the compound is thoroughly mixed. Apply it directly to the area you want to cast and use the tip to stir the compound to remove any air bubbles that may be trapped. It dries in a relatively short time depending on the air and surface temperature. Your cast with the extruder gun will produce very fine detail.
As an example, a twenty-dollar bill is printed on a printing press that would leave an impression on the bill. You can cast the impression of the number "20" on a new twenty-dollar bill. You can also use the extruder gun to lift latent prints off textured surfaces after you have processed them with dusting powder.