Film and Media Overview Nancy E Kraft University of Iowa, Iowa City, Iowa Nancy-e-kraft@uiowa.edu Preservation of Books and Other Media 21-25, May, 2012 IODE Project Office Oostende, Belgium
Daguerreotype 1839-c1860 Direct positive image Preservation of Books and Other Media Daguerreotype 1839-c1860 Direct positive image 1st commercially successful photographic process Produced a direct positive image Used silver coated copper plate Could not duplicate images
Preservation of Books and Other Media Identified by their mirror-like quality, depending on viewer angle, image can be positive or negative Typical exposure was often 60 to 90 seconds long, requiring the subject(s) to remain immobile and hold a pose for all that time Daguerreotype video
Collodion or Wet Plate Negative Process Preservation of Books and Other Media Collodion or Wet Plate Negative Process 1851-1885 Binder made by modifying cellulose found in cotton linters*, potassium iodide, silver nitrate, alcohol and ether Exposure and development of negatives had to be completed while emulsion was still wet Various sizes Hand-cut, glass plates or metal coated with collodion solution Primarily used to make photographic prints on albumen-sensitized paper Replaced by dry gelatin emulsion process Collodion Process video *fibers that stick to cottonseeds
Ambrotype 1854-1870s Collodion solution on polished glass Preservation of Books and Other Media Ambrotype 1854-1870s Collodion solution on polished glass Produced negative image Made to appear positive by placing black-colored paper or metal behind negative Similar in appearance to daguerreotypes but does not have mirror like surface Ambrotype video
Preservation of Books and Other Media Tintypes 1850s-late 1890s Collodion solution on thin sheet of lacqured metal Positive image Small, ½ x ½ to 3 ½ x 4 ½ Tintype video
Preservation of Books and Other Media Albumen process 1850-c1900 Used eggs whites, sodium chloride and silver nitrate Often called card photographs Can have purplish brown, red brown or yellow brown hue Albumen process
Preservation of Books and Other Media
Preservation of Books and Other Media Emulsion: the image-forming layer of photographic films, papers, and plates and is matte in appearance.
Preservation of Books and Other Media Binder: the polymer that contains recording or imaging particles. For example, gelatin is the binder for silver image particles in photographic media. Gelatin: A protein obtained from naturally occurring collagen. Used as a binder for the image layer of photographic materials.
Preservation of Books and Other Media Base: The support of an imaging or recording material on which the recording layer is coated Support: the glass, plastic, metal or paper base on which the image layers of photographic film, prints, or magnetic tape is coated.
Preservation of Books and Other Media
Preservation of Books and Other Media Plastic Supports Acetate: A transparent plastic base for photographic film made by treating cellulose with acetic acid. Term used for various modifications of cellulose acetate – cellulose diacetate, cellulose triacetate… (1909 – present) Nitrate: a transparent plastic base that was used for photographic film. Obtained from the treatment of cellulose with nitric acid. (1893 – early 1950’s) Polyester: A transparent plastic base for photographic film and magnetic tape that is composed of a polymer of ethylene glycol and terphthalic (or naphthalene dicarboxcylic) acid. Very strong and stable. (mid1950’s – present)
Preservation of Books and Other Media
Preservation of Books and Other Media
Preservation of Books and Other Media Degradation terms Acetate decay: Vinegar syndrome. Degradation of cellulose acetate film base that may cause distortion, shrinkage, and brittleness, often detected by a vinegar odor. Silver mirroring: Oxidation of black-and-white images, in which the image silver migrates to the surface, creating a mirror-like appearance. Magnetic shedding: Degradation of the binder of magnetic tape, which results in loss of magnetic oxide particles during storage or playback.
Other “scary” terms: Binder degradation Preservation of Books and Other Media Other “scary” terms: Binder degradation Buckling/Channeling/Distortion/Tape deformation Color balance shift/bleeding/fading/image decay Delamination/Layer separation Microspots Outgassing
Preservation of Books and Other Media Scariest of all System obsolescence: a problem associated with machine-readable images, data, or sound recordings, whereby the information can be recovered only by using hardware or software that is obsolete.
Preservation of Books and Other Media
Preservation of Books and Other Media
Preservation of Books and Other Media
Preservation of Books and Other Media
Preservation of Books and Other Media
Preservation of Books and Other Media CDs and DVDs it is assumed that write-once discs should have a significantly longer life expectancy than rewritable discs Rewritable discs are not intended, and should not be used, for long-term or archival use Should always make two copies as a precaution against failure
Sources Care and Handling of CDs and DVDs A Guide for Librarians and Archivists. Fred R Byers. (NIST Special Publication 500-252 Information Technology) 2003. http://www.itl.nist.gov/iad/894.05/papers/CDandDVDCareandHandlingGuide.pdf Film Preservation Guide: the Basics for Archives, Libraries, and Museums. National Film Preservation Foundation. San Francisco, CA. 2004 http://www.filmpreservation.org/preservation-basics/the-film-preservation-guide IPI Media Storage Quick Reference. Adelstein, Peter A. Image Institute, Rochester NY. 2004. http://www.climatenotebook.org/MSQR/MSQR_home.html IPI The Archival Advisory. IPI’s Guide for the Family Photo Collector, the Genealogist, and the Scrapbook Maker. Image Gallery http://archivaladvisor.org/shtml/gal_phototimeline.shtml
University of Iowa Libraries Iowa City, Iowa Preservation of Books and Other Media Nancy E. Kraft University of Iowa Libraries Iowa City, Iowa email: nancy-e-kraft@uiowa.edu Website: http://www.lib.uiowa.edu/preservation/ Blog: http://blog.lib.uiowa.edu/preservation/