copied with a film, such as Kodak Commercial film. An original with a weak, faded image should be copied with a film, such as Kodak Contrast Process Ortho. SPECIAL  APPLICATIONS  IN  COPYING Special applications are used in copying to detect information that cannot be seen with our eyes under normal  lighting  conditions.  Because  these  are  special applications, they are not performed in most Navy imaging  facilities,  but  are  still  worth  mentioning.  These methods involve the use of infrared and ultraviolet radiation and special types of films. Black-and-White  Infrared Copying  with  black-and-white  infrared  films  and infrared radiation can help in deciphering old, charred, or altered documents. This is possible because similar appearing  materials  can  reflect  and  transmit  invisible infrared radiation in different amounts. For example, two  ink  signatures  may  appear  identical  to  the  eye. However, when photographed with an infrared film, the two signatures may appear totally different. A  suitable  infrared  filter  must  be  used  when black-and-white  infrared  films  are  exposed.  This  is because infrared film is sensitive to visible light as well as  infrared  radiation.  The  infrared  filter  absorbs  the visible light so the film image is produced entirely with infrared radiation. For specific filter recommendations, consult the data supplied with the film or the Photo-Lab Index. Infrared wavelengths are longer than visible light wavelengths and do not focus on the same plane as visible  light.  Therefore,  a  slight  increase  in  lens-to-film distance  is  necessary.  A  separate  focusing  scale  for infrared is indicated on the focusing scale of most lenses. Ultraviolet   Radiation Copying with ultraviolet (UV) radiation can aid in detecting chemically erased or badly faded writing and restoration or alteration of artwork because different materials reflect or fluoresce different amounts of ultraviolet   radiation. Photographing  with  reflected  ultraviolet  radiation in  total  darkness  is  possible  because  some  of  the ultraviolet absorbed by a material may be overlooked as visible light or fluorescence. Such photography in darkness is possible only when a material is illuminated with an ultraviolet source, such as the General Electric Uviarc.  The  fluorescence  from  a  material  illuminated with ultraviolet radiation should be photographed with a No. 2A (pale yellow) filter to absorb the stronger UV reflections. A recommended film to use for ultraviolet photography  is  Kodak  Contrast  Process  Ortho  film. Exposure tests should be conducted to determine the best  exposure  for  an  ultraviolet  copy  setup. Do not use commercial ultraviolet lamps in which the lamp itself is an ultraviolet filter. These lamps transmit visible light that does not permit photographing a  fluorescing  original. COPYING REFLECTION ORIGINALS Reflection  originals  are  documents  or  other  flat objects like pictures or drawings that are viewed and photographed  (copied)  by  reflected  light. Copying reflection originals can be done with either horizontal or vertical copy cameras or setups. The size of the copy setup can range from the space necessary to attach the original to a wall and make the copy photo with a tripod-mounted camera, to a copy setup which fills two rooms- one containing the camera back and darkroom and the other the copyboard. Regardless of the  different  copy  setups  possible  for  reflection originals, the copying techniques are the same with few exceptions. In general, the procedures used for copy work are placing the original on the copyboard, aligning the optical axis of the lens with the original, lighting the original, focusing the lens, calculating the exposure, and exposing  the  film. PLACING THE ORIGINAL ON THE COPYBOARD A copyboard should have a positive means of attaching and holding the original. The means of attaching the original could be spring clips, small bar magnets, thumbtacks or pushpins, a hinged glass frame, a sheet of glass, vacuum, and so forth. When thumbtacks or pushpins are used, be sure not to punch holes in the original. For high volume copy, a vacuum copyboard allows a more rapid change and positioning of originals on  the  copyboard. When you are using a vertical copy camera or setup, a darkroom printing easel may be used to hold the original  in  place. ALIGNING  THE  OPTICAL  AXIS  OF  THE LENS WITH THE ORIGINAL Arising, falling, and sliding front feature of a copy camera provides for the alignment of the lens and the 8-13