Microfilm is a type of film based images. There are many different types of microfilms and versions of microfilm storage. This media is frequently used for long-term image preservation, document reconstruction and offsite storage. As media it has many advantages and disadvantages. The choice of using microfilm will depend on the application and length of time the document or image needs to be stored.
Strength & Stability
Microfilm is much stronger than traditional film as it is made of polyester instead of cellulose. Therefore microfilm breaks less often, and thinner films can be used. The polyester is also more stable and will not change or react with time, humidity or temperature.
Silver gelatin film is used for high-quality images and those that require a permanent record. This type of microfilm has a life expectancy of 500 years. Many times a photo is taken with the microfilm as a permanent record and then the original is destroyed.
Many types of microfilm, including vesicular film and Diazo film will become damaged if exposed to high temperature and high humidity. High heat and pressure will damage the bubbles that create the image with vesicular film. Diazo microfilm will also fade if exposed to light for too long. Therefore frequent usage of this microfilm will deteriorate the image. Storage of the microfilm in a room with a controlled environment is extremely important. Additionally microfilm, is one of the smallest forms of film, so less storage space is needed, when compared to storing traditional, paper documents or photographs.
Open reel microfilm can make data retrieval time consuming as you will need to search sequentially through the reel. Unitized microfilm is preferred as information can be retrieved very quickly. Additionally, open-reel microfilm can become damaged if it is not loaded through the reader properly. The microfilm must be threaded by hand through the reader. Cartridge forms of microfilm have some of the same problems as open reel, though the data-retrieval equipment is much more expensive than the reader for open-reel microfilm. One advantage to this type of data retrieval is that you do not have to worry about the technology going out of date. The system for microfilm data retrieval does not change with technology advances.