.
Expected Life of DVD (Optical) Media
Among the manufacturers that have done testing, there is consensus that, under recommended storage conditions, CD-R, DVD-R, and DVD+R discs should have a life expectancy of 100 to 200 years or more; CD-RW, DVD-RW, DVD+RW, and DVD-RAM discs should have a life expectancy of 25 years or more. Ideal storage conditions are a stable, dark, cool and dry environment, preferably in a sealed airtight container with a dehumidifier such as silica gel to absorb any moisture from the air.
Some sources state that read-write (RW) discs should never be used for archiving: they are not as stable and many may not last 15 years.
Expected Life of Computer (Magnetic & Electronic) Media
Magnetic data (tapes) Up to 10 years
Nintendo cartridge 10-20 years
Floppy disk 10-20 years
Hard disk drives 3-5 years
USB and SD type Flash storage 5-10 years or more (depends on write cycles)
Note that most consumer magnetic sound and video tape is expected to be unuseable by around 2025 due to chemical degradation of the tape itself. For more information see the National Sound and Film Archive's Deadline 2025 report.
Expected Life of Photographic Film
Photographs as we know them first appeared in common use from about 1880 onwards, generally taken with a large format camera on glass plate negatives with the photographer working under a blanket to keep light out of the photographic apparatus. These negatives and prints were generally very high quality images which captured very fine detail and many survive even today in museums and collections.
Silver based (black and white) film - up to 100 years if kept in ideal storage conditions. The most common decomposition process is mould and fungus which grows on and eventually consumes the gelatin based layer that carries the photosensitive silver halide, on the film's base layer. Mould and fungus damage can happen in a very short time in hot humid conditions such as in the tropics, or in an ideal stable, dark, dry and cool environment, may not affect film up to 100 years old. Sydney's climate is generally warm to hot and very humid - not really ideal for photographic film or even magnetic videotape.
Very early photographic film (up to about 1920) was made using a cellulose nitrate base - which deteriorates over time eventually into a brown sticky mess and finallyjust a brown cellulose powder residue. Very little cellulose nitrate based film is still in existence. From about 1920-1950, photographic film mostly used a diacetate base , and from 1950 onwards a triacetate base. Some films from about 1980 onwards used a polyester base.
35mm cameras and 8mm movie came into common use from about 1950 onwards.
Photographic emulsions also deteriorate over time, with specific brands of film being more susceptible than others. Problems such as colour shift, darkening and fading can start to appear - these can be addressed to verying extents, depending on how badly the film is affected, when the film is subsequently captured for conversion into digital formats.
The next most common degradation process is decomposition of the triacetate film base itself which chemically combines with moisture from the air to form acetic acid which gives off a vinegar smell - which is an alarm signal. This process seems to mainly affect movie film and is common for film in the 70+ years age range.
The film usually starts to show a grey crystalline power on it's surface, and the base material shrinks and deforms more and more over time until the film is unuseable for any practical purpose. Again, keeping photographic film in a dark, cool and dry environment will prolong it's life.
Paper based black and white prints made using the silver halide based photographic process appear to be the longest lived form of photographic media in common use so far - again if stored carefully in stable, cool, dry, conditions.
Expected Life of DVD (Optical) Media
Among the manufacturers that have done testing, there is consensus that, under recommended storage conditions, CD-R, DVD-R, and DVD+R discs should have a life expectancy of 100 to 200 years or more; CD-RW, DVD-RW, DVD+RW, and DVD-RAM discs should have a life expectancy of 25 years or more. Ideal storage conditions are a stable, dark, cool and dry environment, preferably in a sealed airtight container with a dehumidifier such as silica gel to absorb any moisture from the air.
Some sources state that read-write (RW) discs should never be used for archiving: they are not as stable and many may not last 15 years.
Expected Life of Computer (Magnetic & Electronic) Media
Magnetic data (tapes) Up to 10 years
Nintendo cartridge 10-20 years
Floppy disk 10-20 years
Hard disk drives 3-5 years
USB and SD type Flash storage 5-10 years or more (depends on write cycles)
Note that most consumer magnetic sound and video tape is expected to be unuseable by around 2025 due to chemical degradation of the tape itself. For more information see the National Sound and Film Archive's Deadline 2025 report.
Expected Life of Photographic Film
Photographs as we know them first appeared in common use from about 1880 onwards, generally taken with a large format camera on glass plate negatives with the photographer working under a blanket to keep light out of the photographic apparatus. These negatives and prints were generally very high quality images which captured very fine detail and many survive even today in museums and collections.
Silver based (black and white) film - up to 100 years if kept in ideal storage conditions. The most common decomposition process is mould and fungus which grows on and eventually consumes the gelatin based layer that carries the photosensitive silver halide, on the film's base layer. Mould and fungus damage can happen in a very short time in hot humid conditions such as in the tropics, or in an ideal stable, dark, dry and cool environment, may not affect film up to 100 years old. Sydney's climate is generally warm to hot and very humid - not really ideal for photographic film or even magnetic videotape.
Very early photographic film (up to about 1920) was made using a cellulose nitrate base - which deteriorates over time eventually into a brown sticky mess and finallyjust a brown cellulose powder residue. Very little cellulose nitrate based film is still in existence. From about 1920-1950, photographic film mostly used a diacetate base , and from 1950 onwards a triacetate base. Some films from about 1980 onwards used a polyester base.
35mm cameras and 8mm movie came into common use from about 1950 onwards.
Photographic emulsions also deteriorate over time, with specific brands of film being more susceptible than others. Problems such as colour shift, darkening and fading can start to appear - these can be addressed to verying extents, depending on how badly the film is affected, when the film is subsequently captured for conversion into digital formats.
The next most common degradation process is decomposition of the triacetate film base itself which chemically combines with moisture from the air to form acetic acid which gives off a vinegar smell - which is an alarm signal. This process seems to mainly affect movie film and is common for film in the 70+ years age range.
The film usually starts to show a grey crystalline power on it's surface, and the base material shrinks and deforms more and more over time until the film is unuseable for any practical purpose. Again, keeping photographic film in a dark, cool and dry environment will prolong it's life.
Paper based black and white prints made using the silver halide based photographic process appear to be the longest lived form of photographic media in common use so far - again if stored carefully in stable, cool, dry, conditions.