Orthochromatic papers and films are also sensitive to yellow light and must be used only with a deep red safelight, not with an amber one.[1] Panchromatic films and papers, nominally sensitive to the entire spectrum, sometimes have a region of minimum in their range of sensitivity that allows the careful use of safelight confined to that part of the spectrum. For example, Kodak Panalure panchromatic paper is tolerant of limited exposure to light filtered through a Kodak 13 Safelight Filter.[2] Other panchromatic materials must be handled only in total darkness.