VHS and audio cassettes in the HIV/AIDS collections are the focus of this week’s blog by our project conservator, Emily:
In the HIV/AIDS collections there are 32 VHS and 46 audio cassette tapes. These cassettes are known as magnetic media as the tape used to carry the information is made from a thin layer capable of recording a magnetic signal which is supported by a thicker film backing. Although these were only formed during the 80s and 90s, they are already showing signs of deterioration. As the materials used to form the cassette ages, the magnetic signal is lost, resulting in a loss of audio and visual quality. This can occur just two years after recording and it is estimated that VHS and audio cassettes have a lifespan of just 30 years. The deterioration of magnetic media cannot be stopped. However, correct storage and handling can slow down the rate of deterioration and reduce the risk of damage due to physical factors.
|Screen shot of GD22/12/24, an advert for the National AIDS Helpline. Shows loss of visual quality.|
GD22/12/30a RSA Advertising. "Take Care" and "Use a Rubber"
Although this stops the data being lost completely, it does not solve the problem. Modern formats of media storage are also subject to the same risks as older media storage systems. The materials used to make the current storage will degrade over time and the equipment used to view the media will also become outdated as technology advances. It is recommended that digitised items be transferred to new formats every five years, making the preservation of digital material an ongoing and potentially costly process. However, audio visual material provides a unique perspective of the past, so it is essential to carry out these tasks to avoid losing the unique information stored on the cassettes.