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Author Topic: Digital dilemma
Jack Coursey
New Member

Posts: 34
From: Nashville, TN
Registered: Jan 2005


 - posted April 05, 2005 09:15 PM      Profile for Jack Coursey   Email Jack Coursey         Edit/Delete Post 
I need some constructive advice of the best way to archive digital photos. I am concerned about whipping out a CD-RW used for storing my jpgs of movie palaces and discovering that either the photo format is no longer valid (like trying to open a old WordStar document from the 20th century) or that the RW format is no longer readable. What’s the best way to insure that when these files are unearthed centuries from now, that there will be a program that can read them?

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Jim Rankin
(Jim passed away in December 2006)
Posts: 123
From: Milwaukee, WI
Registered: Oct 2003


 - posted April 06, 2005 12:33 AM      Profile for Jim Rankin   Email Jim Rankin         Edit/Delete Post 
Jack, you have voiced the big problem confronting libraries and archives across the nation and around the world. With the rapid changes in technology confronting us every decade, it is now anyone’s wonder as to just which of these formats or technologies will survive into the future. What to do with today’s CD ‘s tomorrow is as much a question today, as was the same issue with the old stereopticon cards and the Edison cylinders of the early years of the 20th Century. How many people can view those stereo cards or play the Edison cylinders today? Even the silent films which can, in theory, be shown from older projectors today, are rarely seen at the proper film speed, and many people don’t even know that the jerky depiction of such films today, is the result of faulty projection and a dwindling number of people able to operate variable speed projectors, if such still exist at all.

For your problem, the only foreseeable solution is to store BOTH by means of paper AND some more durable form such as the CD or DVD. At least with these you can view the subject repeatedly with little damage to the image. Storage conditions for these things are the province of the archivists and their publications, and beyond the scope of this Forum, though even minor research in larger libraries and on the Net will disclose numerous discussions of storage. Your wish to preserve digitally for centuries may or may not be realistic, since it is not so much the digits themselves that must survive, of course, but the medium that contains them.

In short, Jack, there is NO guarantee in even decades --much less centuries-- that any technology existing today will exist then. True, there will probably always be some way to retrieve MOST digital records IF there is enough money and willingness present, but I fear as do librarians and historians around the world that much of what we archive in digital or analog format codes (audio, for example) will simply be unusable and therefore discarded when the devices playing them become nonfunctional and it is easier to look at old paper and such film images as survive from the most careful storage. In the case of images, one could use a photo lithographic process that has been around for some years to transfer black & white images onto aluminum sheets, and with some respectable degree of resolution. The hope there is that aluminum will resist corrosion when anodized for this process, but the fact remains that the sheets of metal are thin and prone to distortion or damage in handling. That is why these are usually mounted as keepsakes in picture frames.

As to preserving color images, the analog means are very transient, due to the fact that most all colorants are based on organic dyes, and these are notoriously prone to fading out over time. The only colorants now known to last centuries are the metallic colorants used in such as stained glass or ceramic glazes, but so far these do not lend themselves to normal printing. Gaines are being made in terms of short term preservation measured in decades for dyes, but centuries and millennia are still out of reach. Conceivably, one could find some way to deposit miniscule grains of stained glass into pixels upon a very durable substrate, but just how to keep them glued there for centuries and to make them impervious to weather is another matter.

Sooo, right now, the only real option is to continually make multiple copies in different formats and store them at different locations along with the machines needed to view/listen to them and hope for the best. In reality, the real threat over time is the custodianship of any records after one is long gone from this earth. Even the most important record ever made, God’s Word the Bible, does not have its original autographic manuscripts still existing, and relies upon the fact that it is God’s will that it be copied repeatedly over the millennia, and it is only by His power that such has been done correctly and effectively to this day, yet none of that involves images or sound recordings which would be manifestly more difficult by magnitudes of degree to accomplish for eternity. Nothing lasts forever due to the law of entropy, and only Almighty God is the master of eternity and therefore of anything that is to be recorded. Therefore when approached in reality, one realizes that he can only do so much. Can you set up a legal and financial endowment that would be faithfully paid for and overseen by some reliable funding in a future when inflation and decay may destroy the very funds that you bequeath today? Who knows? I share with you your frustration at this state of affairs when I bemoaned the fact that no full color photos exist from the era of the construction of the movie palaces, yet I know that even if they had had the color still photo technology then, none of the images would have survived into today with true color due to the various means of decay that cannot yet be overcome. Let us hope for sympathetic people in future to take care of our treasures of today, and that they will preserve the means to view digital images, if nothing else. Jim Rankin, former Archiveist/Historian to Milwaukee's PABST theater.

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Brad Miller
Member

Posts: 122
From: Dallas, TX
Registered: Feb 2003


 - posted April 08, 2005 03:24 PM      Profile for Brad Miller   Author's Homepage   Email Brad Miller         Edit/Delete Post 
Don't use rewritable discs. I have always been told that they don't have the lifespan of regular burn-once discs. Furthermore use Verbatim blanks for the best lifespan. (Just buy a small stack of 25 or something and reserve them just for unreplaceable pictures and use the cheapies for regular stuff.) Regardless, every 2 years copy the cds!!! Then 2 years later copy those cds. To be extra safe, get yourself an external hard drive and only plug it up when you are going to archive a group of images. I keep all images I have ever taken (original digital files) in a folder by year. A few times a year I back those up to a second hard drive. It has worked well for me.

The JPG format is pretty universal and should be around longer than you will. Even if a new format comes along, there will always be a way to convert JPGs because there are so many.

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Jim Rankin
(Jim passed away in December 2006)
Posts: 123
From: Milwaukee, WI
Registered: Oct 2003


 - posted April 08, 2005 10:39 PM      Profile for Jim Rankin   Email Jim Rankin         Edit/Delete Post 
Brad is quite right that Verbatim write-once disks will last longer than rewritables, but that is only in the matter of decades, not the “centuries” that you inquired about. And keeping photos on hard drives may be even more problematic than disks, since to be useful one must keep the entire computer as well, and then hope that its micro electronics will work over a hundred years from now (and I can tell you that they won’t. Capacitors are the shortest lived of all the components, and as they fail they allow greater voltages into critical components such as the massive IC ‘s and then these will fail within a nanosecond rendering everything else useless.) Then there is the entire matter of the retention of the magnetic domains on the hard disk, to say nothing of its own internal degeneration that is to be expected even under ideal storage conditions over such spans of time. In the centuries to come, we can only hope that there will be the software to display such images converted to code on the display devices that work then. Remember the scramble to find the few people who knew the old programming codes back before 2000, when everyone was scared stiff that old code formats would wreak havoc after Y2K? The fact that no havoc happened still doesn’t obviate the fact of the great difficulty of finding anyone to even read the relatively simple codes of just 30 years ago, much less centuries. JPEG may be all the rage today, but it will surely be a completely foreign language in a century or more. If you ask your high school kid today what Pascal or Basic were, he will only know that they were something his grandparents knew of and are now only is history books, and he will say “go away Dad; don’t bug me about this ancient stuff.”

Since the best plastic disks of today will automatically degenerate via internal means such as depolymerization, not to mention many external means of decay, the tedious and expensive copying every few years to avoid these problems, may be more than most people can realistically manage. Sad to say, even if you can duplicate the disks every few years and find a really, really secure place to store them and their reading devices, who will faithfully supervise your collection after you are gone --and after he is gone? This brings to mind the account in the prologue to the novel of 1911 “The Phantom of the Opera” by Gaston Leroux, where he relates that the bones of the putative Phantom were found in the seventh subbasement of the Paris Opera when archivists were burying the first recordings of notables of the day in hopes that future generations would discover them. The sad fact is that even if it were true, if they dug those early phenolic recordings up today, they would find cracked and crazed plastic, if it hadn’t crumbled to dust. Trying to outwit time is an exercise in futility.

Jack, you have a noble goal, and I dearly wish you could succeed for the sake of posterity, but I would hate to see you sink a lot of time and money into an impossibility. Don’t take my word for it; do some research on your own. Best Wishes.

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William French, Jr.
New Member

Posts: 22
From: San Francisco, CA
Registered: May 2003


 - posted April 09, 2005 08:25 AM      Profile for William French, Jr.   Email William French, Jr.         Edit/Delete Post 
A good CD should have a shelf life of more than 40 years, compared to the 10-20 year shelf life of magnetic tapes (i.e. VHS and cassette tapes). It is entirely possible that a CD could last 100 more more years. The reason they break down is because of acid contained in the plastic. If heat and/or light is added to the mix they can break down a lot faster.

The one problem that has not been touched upon is the fact that JEPG images are compressed files. When stored on a hard drive they have a tendancy to lose data and eventually corrupt, never being able to be viewed again. I they are stored on a CD, they do not break down because the data on the CD cannot be changed. There is no possible way that data can be lost.

The best possible way to save images in digital format today is on good quality CDs. The format that is used is another story. TIFF and EPS formats have been around a long time and are not compressed. I have seen some archives (like the Online Archive of California {collections from leading libraries from all over California}) use the BMP format. It is stable and I am changing all of my JPG images over to BMP so that I can make sure they are still here years from now.

My vote for long lasting storage is CDs in with images in the BMP format.

Thanx,
William

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Jim Rankin
(Jim passed away in December 2006)
Posts: 123
From: Milwaukee, WI
Registered: Oct 2003


 - posted April 09, 2005 02:09 PM      Profile for Jim Rankin   Email Jim Rankin         Edit/Delete Post 
Mr. French states: "The reason they break down is because of acid contained in the plastic. If heat and/or light is added to the mix they can break down a lot faster." To this might be added that it is not entirely the presence or absence of acid that is the major mechanism of decay in plastics. That mechanism is the exuedation and evaporation of the plasticizers that make plastic what it is. As these solvent-like chemicals evaporate, the plastic becomes a pile of chipped and powered resins that will not hold form. While todays' plastics are much more durable than were the first generations of them, the fact remains that no plastic is forever. The simple truth is that no modern plastics have been around for a century yet, so estimations of their logevity are more the property of the salesman than the engineer. Mr. French is quite right that heat and light will accelerate the breakdown, but then that is true for virtually all substances. Top quality CD or DVD disks may possibly last for 50 years with the most durable coding as he suggests, but we are still nowhere near the 100 years PLUS that Jack imagined. I am not saying that one should not make multiple copies in different formats stored at different locations (an unforseen disaster can occur at any single location), but that if you are going to take the multiple century risk, you should know what you are risking.

The reasons I give here and in previous posts show why the fad of the Time Capsules which started back during the World's Fair in 1930, are bogus in the real, real long run. Fun for the media and the school kids to attend, but few such capsules will really be undisturbed for a century, let alone a millenium.

Science is only starting to understand some of the many internal and external mechanisms of decay, but it is highly doubtful that anything will be around from this century within one thousand years. The pyramids are about all we have from that long ago, and they survived (looted) only because of their massive size on real estate no one in power needed, and due to a most favorable climate. I can't see many pyramids being built for image and video storage hereabouts. Yes, we do have the empty salt mines out west where governments store their master records, but they are now finding that the risidual salt atmosphere is slowly penetrating many of the materials there, and no clear remedy is on the horizon. But, then again, maybe our Jack is a scientist with the time, money and determination to prove the naysayers wrong. Let's hope so!

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William Hooper
Member

Posts: 82
From: Mobile, AL
Registered: Mar 2003


 - posted April 11, 2005 01:37 AM      Profile for William Hooper   Email William Hooper         Edit/Delete Post 
The primary cause of optical disc storage media failure is oxidation of the metallic reflective layer. This is sometimes due to physical damage like scratches, etc., but it usually caused by delamination. The plastic on either side of the reflective layer becomes detached (often because of glue failure), then the metallic layer fails. Archivists were using only gold discs, because gold's lowest tendency to oxidize.

There's a page on CD media at
http://www.colorado.gov/dpa/doit/archives/cpa/articles/audiovisual/careofcds.htm

As Jim Rankin has said, optical disc media has become a headache for archivists, & generally they're only used for access copies. Archivally, digital media is still a struggle, & the best bets are still magnetic media: one popular method is copying to a hard drive, then either constantly monitoring & migrating the information, or, if that's not economically feasible, just removing the hard drive, putting it on the shelf (since failure is usually a function of hours of service), & hoping there'll be an easily available interface available when it's later needed. Making as many copies as possible for archive is also part of the strategy.

Magnetic media still holds up very well -- soundtracks from movies & music recordings are still being produced from magnetic recordings of tape 60+ years old. As the archival community has found out, there's a huge variability in the lifespan of optical disc media, & manufacturers only warranty them for a couple of years.

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William French, Jr.
New Member

Posts: 22
From: San Francisco, CA
Registered: May 2003


 - posted April 11, 2005 07:19 AM      Profile for William French, Jr.   Email William French, Jr.         Edit/Delete Post 
A hard drive is probaly a good choice if you can unplugg it and store it properly, at the right temprature and humidity. The reason the salt mines have worked is because of the low temps and good humidity. But they are not perfect. When one of the George Lucas companies went to get the master print of Star Wars out of storage in one of the mines in the mid 90s, they found that it was severly damaged (not by the mines but by the acid and other chemicals in the film itself). If they would have waited much longer they would not have been able to scan it and turn it into a digital format. Hundreds, it not thousands, of films have been lost because the film disolved over time.

The problem with magnetic media is that what the averge person can buy is not the same as what a profesional can buy. The video tape that TV shows are recorded on can cost more than $1,000 (which is why in the late 70s and early 80s thousands of hours of TV shows were erased so that the tapes could be reused. 80%-90% of Gameshows are gone forever). The average shelf life for a VHS tape that I can purchase at WalMart is less than 20 years. The entertainment industry is switching to digital media because it is both cheaper and lasts a lot longer. The problem with hard drives is that they can be damaged easily if they are bumped or shaken.

When it comes to the chemicals in CDs, remember that acid is a major componet of almost everything. Libraries all over the world are spending millions of dollars to have the acid removed from books and other paper items.

A good question would be, with the new jump drives being able to hold more than a gigabyte each, would they make a good place to store digital information?

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Jim Rankin
(Jim passed away in December 2006)
Posts: 123
From: Milwaukee, WI
Registered: Oct 2003


 - posted April 11, 2005 08:06 PM      Profile for Jim Rankin   Email Jim Rankin         Edit/Delete Post 
To all the foregoing about internal decay mechanisms, must be added the external threats of an unusual nature, e.g.: the situation brought to light when a Florida data storage firm suddenly found its 40000 terabytes of data erased when the radar antenna at an airport 20 miles away was accidentally released from its asmith mount and it fell to point earthward. By the time the techs had got the 400-pound antenna back into position, it had done the damage in an estimated 1.2 seconds. Granted, the odds of such a thing happening are astronomical, but they do point out hazards external to a magnetic medium of storage. True, the data company could have lined its walls and ceiling with Mu metal to shield it, but that is very expensive and how much is needed in thickness for how many unknown watts of penetrating power? Who could reasonably guess?

It occurs to me that if Jack is determined to preserve his images, there is at least one fairly good way, but I do not believe that it is as of yet in color. Notice the next time you walk through a modern cemetary, that medallions with images of the deceased are often there affixed to tombstones. These are a type of fired glaze deposited upon a white ceramic backing, and one could in theory contact the companies making such and pay them to render photos in large format. It would not be cheap, of course, but if carefully stored in such a way as to avoid physical concussion to the ceramic, or scraping of the image, they might well endure for centuries, albiet in black and white. Ceramics are about the most archival of materials, but I have not read any archival discussion about these, but they seem to be possibly the only alternative that resists light, moisture, temperature and casual handling, and have no internal acids and at the same time avoids the dillema of digital reconstruction of the image in the distant future. All digital media will always suffer the dillema of maybe being able to be reconstructed, but a plain visual medium such as the baked ceramic images might be all we can depend upon for centuries -- if no one drops them and earthquakes don't shift them! Best Wishes again, Jack. Please let us know what you decide to do!

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Ken Hamer
New Member

Posts: 5
From: Vancouver, BC, Canada
Registered: Sep 2005


 - posted September 19, 2005 07:27 AM      Profile for Ken Hamer   Email Ken Hamer         Edit/Delete Post 
quote:
the situation brought to light when a Florida data storage firm suddenly found its 40000 terabytes of data erased when the radar antenna at an airport 20 miles away was accidentally released from its asmith mount and it fell to point earthward.
As someone who installs, maintains, and repairs RADAR systems, I can assure you that this is at best an urban myth. There is no way a RADAR system, particularly one 20 miles away, will erase data of any type. Nevertheless, the warning that it's possible through misfortune to lose vast amounts of data is certainly real enough.

But to my original intended point... I read somewhere recently (I think it was a PC magazine or some similar source) that in fact the rewritable CDs and DVDs have more stable dyes, and that some (presumably lower quality) record-once CDs my become unreadable in as little as 6 months. I'm certainly not able to evaluate such claims, and I can't find the article I read. But I'll keep looking.

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