While it is optimal to view moving image materials in order to catalog them, it may not always be practical.  When catalogers do not screen materials, they will have to rely on secondary sources to gather cataloging data.

Although information taken from viewing films and videos themselves should be preferred to data collected from other sources, it is often insufficient for cataloging.  In such instances, research is necessary to complete the cataloging of those materials.

Sometimes the information may not be reliable because film and video titles and credits may have been altered, removed, or lost before the moving image material reaches an archive.  In these cases, research is required to verify the information taken from viewing or to obtain valid data.

Information is included on the bibliographic record whether the information is taken from the work or other sources.  Data is not bracketed unless it is judged to be probable or questionable, or is supplied by the cataloger.

See also: