DigitalQuirk wrote:Again, there is still always tape backup. I shoot all of my family video on mini DV tape for that reason. Hard drives eventually fail, recordable DVD media fades, but good quality tape is the only proven method of long-term data storage. Now, if only I could figure out how to back up my pictures to a MiniDV tape...this might work:
Yes, for my home music studio I still mix everything to DAT. While I keep the mixes on CD-ROM, I still retain the original DATs (which are supposedly really good for archiving stability). Also, even though I'm transferring all my family videos from VHS to DVD, I'm going to keep the VHS tapes as my backup (even though DVD-R is supposed to be better than CD-R for longevity).
It's interesting to point out that while the world is so obsessed with fitting more and more data on smaller and smaller media, this brings with it a great cost. The higher the density of data on a disk, the greater trauma that data can suffer from a small scratch or area of damage. Same goes for small flash drives, etc. More to lose if the chip gets zapped.
That's probably one of the reasons old VIC cassettes are so reliable. It's a relatively low-density data format....so if an area of the cassette suffers a dropout, less data is lost and the chances of recover are greater.
On the topic of recordable optical media, are branded and noname products just as bad when it comes to data durability? One would want to believe that if I spend twice the money to get a famous name, it would last at least twice as long as the el-cheapo CD-R. On the other hand, I suppose the difference between brand and noname never was that large with magnetic media (tapes, floppies etc) neither.
I would certainly trust a good brand name optical media over some no-name brand. Certianly the quality control is better and these companies at least do research and tests on the longevity of the dyes they use, etc.
There are some expensive CD-Rs (FUJI sells one, I believe) that are marketed for 20 or 30 years guaranteed. These are sold for archiving digital photos.
However, even the big names get it wrong sometimes. They realise that despite all their testing and research, a certain dye formulation seems (in real life use) to be failing after several years, and they change their dyes.
Also, there are some brand names which were good in the 80s (Dysan for example, and Memorex) which have really gone downhill. Essentially the name has been bought to slap on a cheap Chinese product. Some of the first CD-Rs I bought in 1999 were Dysan brand. I bought these at a dollar store (should have been a red flag) and after 3 years they were unreadable.
I have heard that Memorex just buys their media from the lowest bidding supplier and brands them with their name. Too bad, because Memorex was a good name in the 1980s. So was BASF, which has really gone downhill too.
It used to be the case with audio cassettes that you could determine the quality of a tape simply by looking at the tape media itself. Cheaper ones were, as mentioned, quite often orange in colour; while higher quality ones were dark brown to black (type II tapes are black). As ral-clan mentioned, some well-known brands went downhill in quality, but you would know that by noticing the difference in colour. A well-known brand that cost more money might cut corners for the sakes of profit, while a cheap underdog or generic brand tape might be of better quality.
With recordable disc media, I have no idea how to determine which ones are better. Comparing some Fujifilm discs (which are supposed to be good quality) to some ultra-cheap Comstars, and the recording surface of either looks virtually identical. I think it might be possible that you'd pay twice as much for a "Better" name, but end up with something that's no better than the discs that cost half as much. Indeed, the "Gold" Maxell recordable CD's that I recorded nine years ago don't seem to be doing any better than the cheap brands from the same era; they scratch just as easily.
DigitalQuirk wrote:1. Perfect way to hide code for spies and hackers.
This brings back memories of Sean Connery in "Diamonds are Forever". After having swapped the computer cassette for a music cassette, he stuffs the computer cassette down the back of the leading lady's bikini.
“Tiffany my dear, we’re showing a bit more cheek than usual aren’t we?
I bought a box of Kodak Ultima Gold 80 minutes in c:a 1999, and they were claimed to last six times as long as the "leading competitors". There is no mention how many years that corresponds to, but the accelerated test environment was 176 F (80 C) and 85% humidity.
How is it with "real" CDs, those who are manufactured using other methods that I don't know the terminology of? Does burning speed make a difference to data longevity?
By the way, BASF no longer exists or at least don't sell media. Nowadays that company is called EMTEC but have the same logotype. I don't know if an buy-out occurred where the new owner got everything including logotype but not the company name, or something else happened. In any case, I thought BASF was so well established and a brand that signify quality, so they wouldn't drop it for no obvious reason. Google probably can give the answer, but I can't be bothered...
Real (commercially produced CDs) are not burned at all. They are a laminated sandwich of plastic-aluminum foil-plastic. The digital signal (in the form of pits and spaces) is actually pressed into the aluminum foil.
So commercial CDs have a really long lifespan - they can't be erased by UV light like CD-Rs.
The only problem is, that if the aluminum layer is exposed to air (a crack or bad sealing of the edge of the disc) then the aluminum can oxidize and you get bit rot on the disc. I think they use a shellac (or something else) coating around the edges of the disc to prevent this.
Yes, I noticed that BASF recordable media has changed to EMTEC (with the same logo and typeface). But I would be surprised if BASF (the chemical company) is out of business. Maybe they just spun off their recordable media line (too bad, they were one of the best before).
DigitalQuirk wrote:1. Perfect way to hide code for spies and hackers.
.......
6. Very long shelf life.
Agreed, agreed and agreed. But tapes are slow, updating a file is nearly impossible and you need an external administration. But because of the above I used tapes as back-up. And even that changed, in 1988 I connected my C64 to my PC (userport <-> LPT) and used the last one as back-up.
I wonder how long commercially produced CDs, if stored properly in a sealed library will last. I don't know how much the actual matrix costs to produce, if we omit the salary for the person doing the work, but for big institutions archiving material for long time, costs should not be an issue.
I've noticed that my VCDs have started to degrade. The end of the movies are now all similarly distorted and even "skip". Does anyone else have VCDs? And the same problem?
How old are your VCDs and what brand of media are they on?
Are they on all the same brand of media?
What are you playing them on?
Did you use a paper label on the disc?
I think it's often likely the last tracks on a disc go first. I can't remember why. Perhaps if you bought cheap CD-Rs they are not sealed at the edges properly and started oxidizing.
It could be an entirely different problem (non-degradation). Since the end of your VCD movies are further from the centre of the disc (where the laser starts reading) maybe it could also have something to do with vibration. If the discs are not manufactured well, and have some sort of slight flutter or warp to them, this can really cause problems at the outer edges of the disc (this things are being rotated at several hundred?/thousand? revolutions per minute). So in that case it could be a laser tracking problem. Copying the disc might solve this.
Also, if you play a slightly warped disc, or a disc with a paper label, it can cause problems in laptop drives (not very roomy in there).
My laptop causes problems with some discs due to heat and the confined space. It heats up the disc slightly and causes it to go (temporarily) slightly concave, resulting in read errors on the outer tracks (until the disc cools down).
It is always at the end of the movie. Most of the discs (if not all) are not labeled and were bought in Hong Kong (probably cheap quality discs)... I wish I had copied them before this happened!
A few were already messed up when I got them. The image will start to freeze and stutter, eventually turning into blocky patches of images overlaping one another.
I've experimanted with different players and got pretty much the same results. I am going to try playing one on the computer and see if it is any different.
Do you think there is a way to rescue the data from the VCD?
Well, I think NERO and some of the other more advanced burning software might have a "SLOW, ACCURATE" ripping mode. I.e. they rip the CD at 1x and try several times to read the data.
G'day, mates!
Here's a tip for loading cassettes. For years my favourite game on the 64 has been Boulder Dash. However, the cassette has always had trouble loading no matter how much I clean the heads, realign, etc. So, this is what you do: When you "press play on tape", hold both hands over the Datassette and start PRAYING that the game will load. I find a nice little chant works well. Talk to the Datassette in soothing, unthreatening tones and NEVER yell at it no matter what! You may well dismiss this advice at hocus pocus but in a test that I carried out, the tape loaded SEVEN OUT OF TEN TIMES with the "hands on" approach and only three times out of ten without it! GOD'S TRUTH!
PS: Only use this method as a LAST RESORT or your girlfriend will think that you're REALLY nuts!
PPS: Yes, I'm Australian.
