On Mon, April 28, 2008 00:34, Trevor Cunningham wrote: > Here in lies a reason to prefer film over digital. Magnetic storage is > far more unstable than sleeves and notebooks. Burned storage has a > suprisingly limited shelf life, so we are learning. You can still play > your cd's from the early 1980's, but the commerically produced materials > are much higher quality than anything you can to make yourself. > Indeed, digital is less expensive...but, then again, it's cheaper Let's see; the first counter-case that comes to mind is the photographer who died in the WTC attack. The film in his film camera was unrecoverable, but all the images on the flash memory card were recovered. There were also a collection of important negatives of the Kennedy family in a safe-deposit vault under the building; you may have seen the book, made from prints and contact sheets sitting around that photographer's studio. If the data had been digital, there could have been more than one copy, and it likely would have survived. Film in sleeves and notebooks is degrading every single second it exists; most especially color film. I've got works I shot myself with notable color shifts and density loss. You have to go to controlled-humidity low-temperature storage to come anywhere close to stopping film degradation. Mind you, that can be as simple as a refrigerator and zip-lock bags, perhaps with silica dessicants in them (I haven't tried to do this and haven't researched current thoughts on best storage conditions). It also makes access slow and somewhat painful, and risky (open the bag before it's warmed up and water will condense all over your valuable negatives). I've been using Kodak Gold Ultima CD-Rs, and more recently MAM gold archival DVDs. So far no disk I've tested has shown any significant increase in error rates. Counting Kodak Photo CDs I got made, I have examples going back to around 1994 that I keep checking up on. (The data is also on multiple hard drives, and on more recent archive disks I burned, but I like to check up on the older samples just for curiosity.) These disks claim lives in the 200 year range -- obviously based on accelerated testing rather than natural aging. In *that* timespan, I don't expect DVD readers to be available any more, and I think file format changes are pretty likely too. Digital archives work wonderfully *when competently managed*. They are *horrible* for long-term benign neglect. The ability to store multiple copies in separate locations gives you the ability to protect against problems that are intractable in analog (where copies are not only expensive but *inferior*). Analog media degrades constantly over time, but sometimes fairly slowly. The right analog media do pretty well with long-term benign neglect. So what I see here is that they have different characteristics, and so one is better for some things, the other is better for others. -- David Dyer-Bennet, dd-b@xxxxxxxx; http://dd-b.net/ Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/ Photos: http://dd-b.net/photography/gallery/ Dragaera: http://dragaera.info
