What are the industry standards for image brightness and screen reflectivity?
According to the Society of Motion Picture and Television Engineers (SMPTE), the generally accepted standard-setting organization for the industry, films are to be projected at a brightness level of 16 footlamberts (+/- 2 footlamberts). There is no standard for screen gain, and it varies substantially from theater to theater (from 1x to 3x is common). Screen gain deteriorates over time, and thus requires that screens be replaced periodically.
