Preservation Interest Group

The March 27, 2018, Preservation Interest Group meeting was attended by 17 people representing a number of Capital District institutions including Albany Public Library, Guilderland Public Library, Hudson Valley Community College, the NYS Archives, the NYS Library, the NYS Department of Environmental Conservation, the NYS Military Museum, the Schenectady County Historical Society, and the University at Albany Libraries as well as students from the University at Albany's Information Science Masters Program.

Facilitators Ann C. Kearney and Karen E. Kiorpes, both from the University at Albany, started the meeting by introducing their colleague, Mark Wolfe, Curator of Digital Collections. Each attendee then introduced themselves and briefly discussed their AV concerns and questions which included identifying the proper format for digital storage of AV material, copyright restrictions for transposing VHS to DVD in academic collections where DVD or digital copies do not exist (see §108(c) of the U.S. Copyright Act), playback options for reel-to-reel tapes, in-house vs. outsourced digitization or repair of AV material, necessary digitization and playback equipment, and storage options, etc.  There was also a show and tell aka "what is this weird thing?" There's a link to the document "Texas Commission on the Arts in 2004: Video Identification and Assessment Guide" located in the resources box below.

The meeting concluded with the attendees recommending a follow-up discussion on AV be held, possibly in early July.  It was also announced that the topic of the next meeting would be "binding options."

General Information

Mark addressed the initial question of proper AV format by saying that MP4, a compressed audio video format, is fine for storing AV.  This format is used for online streaming and can be uploaded to YouTube, and has the ability to store subtitles for the video.  This lead to a short discussion about the YouTube option that creates editable closed captioning for accessibility purposes. The takedown of  UC Berkley's Public Access to Educational Media in 2016 was referenced. He then went on to say that if you asked the same question to a different person, you would probably get a different response due to a lack of definitive agreement on the proper format (no .tiff equivalent in the AV world.)  For material that is purely audio, the digitized file should be saved/stored as a .wav file which is uncompressed or lossless.

Next, the group discussed how to look at film reels (always use gloves!)  In order to determine whether the film includes sound, you can examine the film itself.  If a soundtrack is included you will see it located between the perforations and frames.  A mono soundtrack will have one line, stereo will have two. With magnetic film or video, however, it is impossible to determine what the tape contains without the help of some sort of playback device.

The group then discussed pros and cons of outsourcing the digital preservation or doing it in-house. Outsourcing the work can be an option when dealing with material that is fragile and/or rare, or when there is insufficient staffing and/or resources. However, since vendors can be costly, it might make more sense to purchase some basic equipment and take on the work yourself. This, of course, has its own set of costs as it can be more time and resource consuming. A list of vendors and equipment are located further down on the page.  

Identifying Problems

There are a number of things you might encounter as AV material degrades.  However, different types of AV material will be subject to different problems, but overall proper handling and storage of material will help keep the damage to a minimum.  Each heading below is also a link to the National Archive webpage about that format.

Motion Picture Film

Most film is composed of two basic layers, a base made of transparent plastic, and an emulsified layer that holds the image.  The base is typically made of either acetate or polyester.  Damage can occur when the film has been improperly handled or stored.

• Physical damage like broken leaders and sprocket holes can typically be fixed with the proper tape.  Scratches to the film are more difficult to repair so it's important to make sure the machines used to playback material are clean.  A Q-tip or cotton swab was passed around.  This along with rubbing alcohol should be used to clean playback heads to make sure they are clear of dust and dirt.
• If a film is stored in humid conditions it can become a host for mold, mildew, and fungus.  In this case, the film would have to be cleaned and moved to the proper conditions.  This type of damage typically affects the emulsion layer.
• If your film smells like vinegar, then it is probably a case of acetate decay or vinegar syndrome.  This can occur when the film is exposed to hot humid environments.  The backing of the film will eventually shrink and become brittle leading to the emulsion cracking and flaking off.  One way to stop or slow down the process is to freeze the film. This type of damage cannot be reversed.

Magnetic Tape 

both Audio and Video

Magnetic tapes can either be stored in open reels or within cassettes and cartridges.  You cannot see what information is stored on this type of medium without the help of a translator or playback device. Magnetic tape typically also consists of an acetate or polyester base layer but instead of an emulsification layer, magnetic tape has a binding layer that holds the magnetic particles made of iron oxide. Tapes might also include a back coat layer.

• Acetate backed magnetic tape can be subject to vinegar syndrome just like with film.
• The breakdown of the binding layer, often due to the absorption of moisture,  is called Sticky-shed.  You will typically hear squealing or a screeching sound when rewinding the tape and/or during playback. This sort of problem can leave residue behind on the tape heads, so again, it is important to clean the heads after or before use. One temporary solution to this problem is to "bake" the tape.  When this is done, the heat from baking removes the moisture and usually results in a tape that can be copied for preservation. Acetate tape should not be baked. 
• Demagnetization: preventative measure can be taken including maintaining cool and low humidity storage temperatures and demagnetizing playback machines between uses. Demagnetizing tape heads and guides can also prevent Print-through.
• Print-through can happen in high/fluctuating heat environments or when tapes are stored improperly and sounds from one layer of tape bleed through to the next.  This can be avoided by storing tapes and reels tails out. Tails out is when the beginning of the tape is closest to the core (the tape has been played to the end and then stored.)  The tape would have to be rewound in order to play from the beginning on the next playback.
• Tip: Make sure to knock out the locks on cassette and videotapes to avoid accidentally taping over them. See this article on write protection.

Gear and Applications

It was recommended that most digitization could be accomplished using the open sourced software Audacity.