Giving a job description of a cinematographer is a bit difficult because the term cinematographer can apply to various jobs ranging from camera operator to director of photography. Most often, the term refers to the director of photography, or top cinematographer on a film, so let's focus on that.
Thermoplastic Polyolefin Elastomer (TPO (POE)). Thermoplastic polyurethanes (TPU) are a class of polyurethane plastics with many useful properties, including elasticity, transparency, and resistance to oil, grease and abrasion. Technically, they are thermoplastic elastomers consisting of linear segmented block copolymers composed of hard and soft segments.
A low-. pressureflowofdrynitrogenshouldbeusedwhenbrazing. lineconnectionsinthefieldtopreventoxideformationon. the interior walls of the copper tubing. POE lubricants. used in R-410A systems are a form of a mild organic acid, which scrubs oxides and contaminants from the interior. of refrigerant tubing walls.