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Say Goodbye To Your CD-Rs In Two Years?
Little Hamster writes "According to an article on cdfreaks.com, a test done by the Dutch PC-Active magazine showed that among 30 different CD-R brands tested, a lot of them were already unreadable after twenty months. This is shocking, and makes me wonder how should I backup my data, photo and music collection."
The CD is an inferior storage technology that has propagated due to 3 reasons IMO.
1. For the average person, a file is in some way less real if it is on a hard drive, and more real if it is on a CD, where it is a physical object they can touch.
2. Familiarity with CD's due to long term use on music CDs.
3. Vastly superior marketing to hard drives.
Removable hard drive bays should be standard on all PC's. Once you are used to these, the Hard Drive is just a Cartidge to plug into the PC. Data is easily backed up, and a Hard Drive in closet is safe.
Hard drives are faster, take up less space, and are very cost competative with CD's. I am unclear why CD's are popular with the tech savvy crowd. It's an inferior storage technology.
HenryJamesFeltus.com
I tend to keep a lot of my recorded CDs on the floor of my car, rolling around loos.
Is that not an optimal storage space?
..........FULL STOP.
You can buy special transparant stickers for that. They cover almost the whole CD. You need a tool to stick them on properly. See here.
-- Cheers!
...and I have heard this, too! all the *not-illegal* backups of my audio cds that I listen to in my car are damages within 1 month or so. This, despite keeping them in a cd wallet :)
Of course, since cds come cheap, I dont mind throwing away the scratched cd and burning a new one. But what about the environmental cost? 3 -01-13-ct-cdcare.html
btw: I found a decent link for taking care of cds:
http://www.aarp.org/computers-howto/Articles/a200
People have already posted they've had write-once CDR media last for years; I myself have media I created nearly a decade ago which doesn't show any (obvious) signs of degradation; admittedly I can't see in that cool color spectragraph they've produced (how did they make that, anyway?).
;) but my original 2^2 writer still works everywhere, including DVD players and portables (and, more importantly, on other peoples DVD players and portables). My own experience suggests that the burner is the more important factor then the media -- you can spot bad media right away because you start producing coasters at a higher rate.
The only problem I've observed over the last few years is problems between CDR hardware vendors. People bring me something they've burned on their new 52 speed writer and it only works on their reading hardware (or, more accurately, doesn't work in mine
If the price for faster burns or newer vendor equipment is a short(er) media shelf life, I'll stick with my original stuff and grow a beard instead.
"Please discuss this subject in our Media Forum."
Damn, your're right!
Does DVD-R last longer? Let's see, I'll need about 200 blank DVDs...
You can do the experiment, but you will need a cheap-o-media try burning at 1x and then at the maximum your CDR drive can handle, and try it on a variety of CD-ROM drives, the odds that the 1x copy will be readable on more drives.
I still have a SONY CDR burned at 1x in 1997 ! and still works just fine. (but useless old software anyway)
I agree.. Slower recording speeds will usually improve the contrast ratio of the resulting recording.
One can confirm this by making several cd-r's writing at different speeds using the same type of media, and then visually comparing the cd-r's data surfaces, (For recorded areas, Darker is better).
A fair number of CD recording programs DO NOT have a VERIFY cd-r contents option after a burning, and is a major pain in the ass. This problem got me good when I used some 12x Office Depot media for saving some TV show mpegs. Bad move, :-(
I found out months later, that 50% of initial recordings had one or more non recoverable bad spots.
Nero is the only mastering program I know of, which will verify cd-r contents after burning :-),
:-( .
But it doesn't do it for all recording formats
Same experience here, some brands sometimes don't pass the year alive!
e s/recover cd.sh /. inserts, if any) :)
To try to recover the most of possible from cds (in data mode only), i have written a little shell script, basically it reads byte per byte (i know i should use blocks of 2048 but that was complicating the rest), if it fails on a reader, it asks you to put the cd in another one, etc
Some readers can read parts of damaged/old cds better than others etc... 2 cd readers required!
here is the link to the script:
http://lethalwp.dyndns.org/~lethalwp/fil
(suppress the space
i won't update the script any further.
If you're on the Mac, the Finder's built-in burn verifies, as does Disk Copy, though, to the best of my knowledge, iTunes does not, but it will terminate on a bad burn and let you know about it. Roxio Toast also verifies.
Option-Shift-K.
Too bad they didn't give a list of brands and manufacturers; that would've been good to know.
... the Mitsuis at up to $5+ per disk at times). Unfortunately I
believe they dropped off the CDR market since I can't seem to get a hold of any
of theirs, save some which is rebranded under a different name... which you
really can't find out until you pop it into the CDR drive to ID it.
I believe Taiyo Yuden made a well-stabilized cyanine die that was supposed to
last long as well.
I can't say much about the stability of the pthalocyanine dyes today, especially
all those coming from the cheaper manufacturers (Ritek, Prodisc, etc). It
doesn't seem like you can even find gold pthalocyanines anymore these days, or
heck, even gold cyanines. I don't know much about the azo dyes though.
Back when you could still get them, I burned all my important data onto Mitsui golds. They seem to be working still, after sitting around for 5-6 years. Similarly with the Mitsui silvers and Kodak silvers. All these used a pthalocyanine dye, which is supposed to be more stable than the cyanine (and cost more
Which brands are good today? That's rather hard to tell, since even within a single brand you're probably going to find a bunch of different manufacturers, unless you're buying one where the brand is the same as the manufacturer. I've seen tons of different manufactured Sonys; Taiyo Yuden's and Mitsui's showing up as Memorex's (very rare, most of the current ones are Prodisc I think and I've seen a lot of Riteks in the past). 'Made in Japan' seems to be a good sign though, instead of 'Made in Taiwan'.
Personally, I save the cheapo ones for throw-aways. Burn to listen in my car for a while, to mix and match and avoid wear and tear on originals. Scratching them up really doesn't matter, they're not that critical. Anything important I try to keep on (supposedly) more long-lasting media, and that gets handled with care. So far, 5+ year backups have been brought back up and data read without any problems. Whether that'll be true of the more current disks in another 5 years I really can't say.
-- Silhouette
You mean you don't back up your porn to your $5,000 autoloading Exabyte SCSI tape drive?
>> "Two words: Taiyo Yuden"
I've bought nothing but Taiyo Yuden discs for the past 2 years, and have the learned the hard way that they aren't any better. Many discs that I've burned over the past 2 years have become unreadable in as little as 6 months. These discs were stored in jewel cases, in a drawer, and handled carefully (not used as a frisbee or coaster).
I've even tried burning at lower speeds, (i.e., burning at 16x even though the discs are supposed to support 32 or 48x) thinking that maybe this would give better stability, but no such luck.
The cost of CR-Rs has dropped enormously over the past couple of years, to the point where even "premium" brands like Taiyo Yuden can be had for 30 cents (or less). And now we see why -- just like hard drives, the decrease in price is more the result of a reduction in quality than an increase in technology.
Although they are of a similar tech, what about DVD recordable disks? I've got plenty of those now...
This would be as good a place as any to mention TDK's Armor Plated DVD Media, which are supposed to keep on working even after having been scoured with steel wool pads. Also, Verbatim makes a line of scratch-resistant CD-R media.
There are two kinds of people: 1) those who start arrays with one and 1) those who start them with zero.
Good idea. Not being a chemical expert, I visited an industry leader to gain a chemical enginnering degree and learn about the latest in organic dye technology. E2 taught me Quantum mechanics so another prevention method is now obvious.
Take a burned disk and a blank one and rub the 2 together. Rub vigerously, we need to entagle a good number of them 'purty quantums. Now re-burn the same stuff onto the blank disc as the written one. Easy eh?
Try to ensure you use the same image and burner otherwise you'll get a ghosting effect of the data and you'll have to re-orientate your antenna.
CDRs are much more reliable than hard drives. Each hard drive has a high probability of failing in the first two years. That's likely why the warranty on new drives was recently reduced to 12 months. CDRs, if they are high quality and are properly stored, can last many years.
This Site has been kicked around slashdot lots of times and depicts a man, a dremel, a CD and 30,000 RPM's of angular velocity.
[Fuck Beta]
o0t!
+Funny, yes. But it might actually work when you embed the data into real pictures/movies. The technique of embedding is known as "steganography", and sometimes also as "digital watermark".
.WAV files. You could choose to use only the lower 4 bits (WAV 4x as large as hidden data) or the lower 8 bits (WAV 2x as large as data).
Scramdisk was an open source program to create encrypted containers (mount as driveletter in windows) in
Be the first to post a FLAC (lossles audio compressor) of the next hot EMINEM album, with some 200 MB of your personal encrypted backup hidden in it, and your backup will live forever!
Marc
Rather than snippets, here is a reliable translation of the entire article.
"
CD - R garbage (September issue)
Tuesday 19 August 2003
CD-R unreadable within two years
Random sampling provides worrying results
Jeroen Horlings
Imprtant data on a cd-r are in practice not always easy to keep. From our practical test, published in the September issue of PC-Active, it appears that data on a cd-r may become unreadable within two years. It is very likely that by using certain cd-r brands important personal information may be lost.
As you probably know, as a reader of PC-active, we tested quite a few cd-r in 2001 and we then published the results. It appeared then that new cd-r sometimes did not conform to standard quality requirements. We kept the thirty different branded cd-r which we tested in a locked cupboard. Before this article we tested these cd-r again with a professional cd-r analyser which watches to an extreme precision what is the current condition of the cd-r.
On this image you see exactly the same cd-r. On the left you see the result of the test in 2001, on the right the same cd-r in 2003. Colors express the seriousness of the error in the order of white, green, yellow and red. This represents easily readable (white) and unreadable (red).
From the test it appears that a number of cd-r had become completely unreadable and that with other cd-r the data had become partially unreadable. Data which had been put onto the cd-r twenty months ago had become unreadable. These were c-dr of both known and less known manufacturers.
It is assumed in general that cd-r at least remain usable for ten years. Some manufacturers claim even a usability of a century. From our sample testing it seems that there is lot of garbage on the market. We have found cd-r which should have never been placed on the market. These came possibly from unreliable suppliers. It is unacceptable that cd-r content has become, within about two years, totally unusable.
In the September issue of PC-Active, available on 22 August, the shocking results are described in detail. Besides the possible reasons for the data loss with passing of time we provide also a number of useful recommendations to preserve data on a writable cd. On the free cd-rom there is also a program allowing to assess the status of a cd-r.
[ i ] PC-Active September 2003
(available from 22 August)
EUR 6,99 (including free cd-rom)"
I am afraid I don't find this exactly mind-boggling. Perhaps over here in Europe we are more critical of stupid manufacturers' claims...
Thufir Hawat
Part-time Mentat
Do a full backup once a year and a 20 month lifespan for the media doesn't matter...
Ahhh, any veteran of the Commodore 1541 floppy drive can tell you what this is: alignment errors. You see, the head is moved using these little step-motors. With use, the motors drift out of alignment, meaning the head moves somewhat less (or more) per "kick" than it's supposed to. As long as it's the same motor, that error occurs on every operation, so there's no net effect. (That is, sure, the data's in the wrong place. But during read-out, the head will seek to the (same) wrong place. So no error.) But move that disk to another machine, whose step-motor has a different alignment, and BAM! read errors.
Fans of the C1541 will remember what happens when that drive found an alignment error: CLACKETY-CLACKETY-CLACKETY-CLACKETY-CLACKETY-CLAC
The Mongrel Dogs Who Teach
I suspect that CD drives also have this capability, just that software doesn't bother to use that info. Actually, most software doesn't even appear to check for non-recoverable errors so I suppose it's being consistent.
The drives we use to backup our systems write at a sustained rate of 30-40Mb/second each. The fast drives are expensive though.
Government of the people, by corporate executives, for corporate profits.
However, others have noted that real-life disks can have a much shorter life.
Normally I'd reckon that off-brand disks come off the same production lines as name brands, but Maxell currently has a campaign to warn people that some white disks are digitally marked as Maxell, which can lead to a recorder treating a disk as a 4X when it's actually a 1X. So perhaps one should stick with branded products for archival purposes.
TDK claims to be using a more stable cyanine dye now, which should translate to increased storage life.
As a rule of thumb, disks recordable at higher speeds should have a longer storage life than those limited to 1X, since improvement in dye stability is directly responsible for the increased recording speeds.
And what kind of dye did the CDs use?
I remember when I was first investigating what brand of CD-Rs to buy. I read an article on the differences between the dyes used in CD-Rs.
Don't remember the exact details, but it was something along the lines of the chemical combination used to make CD-Rs with green dye are better for single speed reading (eg. Audio CDs) but didn't last as long. The chemicals used to make the silver/gold dye however were superior for data, and should last somewhere in the order of 20 years. I think blue dye was somewhere in between.
This similar article says gold dye CD-Rs have 100 year durability, and the cheaper green ones only have a 10 year life, but have been enhanced to give 20-50 years of service.
According to this CD-Recordable FAQ entry , "it depends".
Fuck the system? Nah, you might catch something.
I used to work in a CD factory (from 1986 to 1994), and this is plain not true. A pressed CD consists of:
disc label
protective coating (laquer)
Aluminum layer (sputtered on)
data layer (pressed into the next layer when injection molded)
polycarbonate injection molded disc
To vary from this is a violation of the Phillips spec, and you are not allowed to put the Compact Disc logo on the resulting product.
What you probably noticed was the laquer layer was thick when we started making discs, but over the years laquer has improved to the point that only a very thin layer is needed.
If you leave out the laquer entirely, the aluminum oxidates rapidly, rendering the disc useless.
Do you remember science class where they told you a measurement wasn't correct unless it included a +/- error estimate?
Every CD burner (like every real-world device) has a certain amount of error. The device decides to turn the laser on or off, and there is a delay before the laser turns on or off. This small delay varies with heat and other factors within the device and varies with the component tolerances from device to device.
This error rate is over time, not distance. So, if the CD is rotating slower, it doesn't move as far during the error period. This results in a burn which is closer to perfect, that is it has less error distance than a higher speed burn.
Then there is the completeness of the burn; with a brand new good quality drive it shouldn't matter, but how many of you have a brand new plextor?
And of course there's also the CD media. If you bought the 10 cent bulk discs and expected them to last, shame on you. I record at slow speed to the old dark-blue verbatims whenever I can, and after 7 years I havn't lost data yet.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
Did you ever look into CD-RWs?
They are a phase-change medium, either the substrate is crystalline or it is amorphous. Thats not something that's likely to change with time or degrade like an organic dye.
Starman97@Gmail.com (bring it on spammers)
Is it just me, or does this floopies/beeb thing sound distinctly pornographic?
experimental audiovideo minimalism: Rebuild All Your Ruins
Remember, don't leave your CDs in the car for more than about a fortnight, or they will metamorphose into 'Best of Queen' albums.
Why does every porn joke get instantly rated "5, Funny"?
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
Well, give it up. What brands have you used that are fine, or more importantly, what brands have failed for you? Here's my experience:
Lesson 1: Never get a CD-R w/o any printing on it. I got some (TDK, I think) that were just silver on the top, no branding or anything, and they burned just fine, but I found out later they could be scratched VERY easily. Scratched on the top, mind you. Apparently there was no protective layer over the foil, and you could just scratch it right off. I think they were meant to be printed on by some kind of CD printer.
My TDK's that I burned 2 years ago with the white surface (w/ branding) seem to be perfectly fine though. I also don't seem to have any problem with any imations that are as old.
I have one 2-year-old CD in which the foil appears to be harboring some kind of fungus. The brand is "K Hypermedia," I think I got it for free or really cheap. You probably get what you pay for. But the "fungus" is only on part of the edge, so it still plays fine. I have a handful of others of the same brand, which look okay.
disclaimer: I take semi-good to pretty-bad care of my CDs. They are routinely left out on the counter, desk, or wherever, and sometimes stacked in tall piles, when I don't feel like looking for the matching packaging.
c-hack.com |
Priorities, my man, priorities!
Why does every porn joke get instantly rated "5, Funny"?
I'd explain, but it takes too long given that I'm typing one-handed.
Opinions on the Twiddler2 hand-held keyboard?
According to this site that was linked to from Fujitsu's site magneto optical drives are nearly indestructable, they have a minimum life of 30 years (good enough for me) they don't lose their magentic properties until they reach 180C so you can spill as much coffee on them that you want. =P
The drives can be had for roughly $257 for internal IDE. I didn't shop around hard, but you can get a 5pack of 1.3GB disks for $95 that's about $0.014/MB, not too shabby. They also make high end solutions with 9.1GB disks but the drives are remarkably expensive. If I were more serious about doing backups, magneto optical would be the way to go.
Fear trumps hope and ignorance trumps both
Yes, but the original poster is also corerct, floppies bought today are total crap compared to years ago. Every floppy disk I've bought in the last few years have all been unreliable at best, but floppies I bought 10 years old still work perfectly.
True story:
I had a 1541 that wouldn't stay aligned for more than a couple of hours. One day, I smacked the drive in pure frustration while it was gronking away - and the sonofabitch loaded.
From that time forward, SOP for loading any C=64 program was:
1) load *,8,1 [enter]
2) watch drive light come on
3) swat drive
4) PROFIT!!!!
DG
Want to learn about race cars? Read my Book
Are you a VF grad? Check out the VFMA Alumni Forums VFMA Alumni Forum
Are printers and scanners good enough to make it worthwhile? I don't know. I haven't run any tests and I don't even have a good feel for how many bits you can print on a square millimetre of paper and scan back reliably.
But let's pretend we can print and resolve three pixels per millimetre and 3 levels each of cyan, magenta, and yellow per pixel, and that we're using A4 paper with 10mm margins.
bash> bc
bc 1.06
Copyright 1991-1994, 1997, 1998, 2000 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY. For details type `warranty'.
ppmm=3
bpc=3
bpp=3*bpc
margin=10
width=210-margin*2
height=297-margin*2
bytes_per_page=width * height * ppmm^2 * bpp / 8
bytes_per_page
532878
bytes_per_page/1024
520
Damn, just 520k for a whole lot of trouble, paper, and ink.
But, as I say, I don't have a good feel for what bpmm and bpp really are. Does anyone know? Has anyone heard of any attempts to actually do something like this?
Fuck the system? Nah, you might catch something.
Long story short the rule of thumb was like this: Green CDs have a life of ~5 hours. Yellow CDs ~20 hours. The DARK DARK Blue cd's (not light blue, the only brand I know of like this is Verbatim) *600* hours.
The price increases correspondingly as well. I found the best solution was to use blue's for backups and critical things, and regular commodity cd-r's stuff for day to day things.
Religion is a gateway psychosis. -- Dave Foley
That article is like those tv news ads, like the one from Simpsons where Kent Brockman said: "A leading brand of cola causes cancer, but we won't tell you which one till you watch the show!"
Well, where is the list of CD-R's that will go bad? I couldnt find it on the link, anyone have a quick list?
The machine is usually a Sony CD-RW CRX145E, recording at 10X and re-writing at 4X. I have faster burners on other machines, but those are newer, so I can't yet vouch for their quality.
Here on Slashdot there are many things that divide us, emacs vs. vi, SuSE vs. Debian, the best Dr. Who, all sorts of geeky crap. There is one thing that unites us all- our love of pornography.
-Barry
Why is everyone surprised? The only means of data storage that has been tested to last 100+ years is to write it out to paper. For extremely critical stuff, it's typically printed in a small font on acid-free paper, then stored in a climate-controlled vault.
Or any of the other dozen companies doing this that have folded in the past 2 years.
Programming can be fun again. Film at 11.
Sorry paper rots over time, and there is always danger of a fire. The ultimate backup is cuneiform on clay tablets. They remain readable after thousands of years.
Quemadmodum gladius neminem occidit, occidentis telum est
I've always wondered if this [burning at 1x speed results in better CD's] is actually true or not.. I have yet to see any actual evidence to back up this claim...
Well, head on over to cdfreaks.com website and take a look at the results of some tests. For the lazy among us, burning at 4x resulted in more C1 errors in every test posted (on page 1, page 2 timed out) than burning at a higher speed (usually 40x, but one test was at 52x). A comment on page 2 indicated on person did 4 tests, and half said burn at high speeds and half said burn at lower speeds. Overall, the small sample of results indicated that burning at low speed usually makes things worse, not better. Surprising huh?
I still have the two CD-Rs that were included with my first CD recorder I bought about 10 years ago. They are hp brand and were recorded 2x speed. Both are working fine.
Not that there is anything of interest on them of course. At least if you are not interested in Winzip 2.0 or something of similar age. I just keep them out of curiousity how long they will be readable.
RedShirt
Microsft spel chekar vor sail, worgs grate !!!
I remember way back when, around when CD-R's first came out, they had a type of organic dye that appeared gold whos purpose was for data archival. I have a few of these and quite a few of the old blue Verbatims and some no-name green media. All of these are still quite readable, and they were burned in 1996. Perhaps one of the reseachers in the article left their CD-R's on the dashboard of their car and didn't own up to it.
. shtml
The other thing to consider is that DVD-R/+R technology is dropping though the floor. I bought a Pioneer A05 for $320 in January and today the A06 is going for $229., and remember I bought this thing from the same place I linked to. I don't know how DVD-R is for archival, but my point is that at the rate the technology is falling in price, CD-R may not be around much longer anyway.
In any case, I found a rather excellent guide on the different tyes of CD-R media. It goes over all the dyes, their manufacturers, theoretical lifespans of the dyes, etc. I recommend a visit...
http://www.cdmediaworld.com/hardware/cdrom/cd_dye
-R
I haven't had any high quality CDRs go bad on me yet. And by high quality I don't mean your bulk spindles, I mean Mitsui Gold, Tai Yuden, Kodak Gold (no longer produced), Verbatim DatLifePlus (stay away from ValueLifePlus), etc...
To be extra safe, I run two CD-R drives to write two copies of the data to two different brands of CDR medias at the same time. Then I also overlap the data for the next batch -- taking half the data from the previous CD, and adding new data to fill the new one. So that any given data is on no fewer than 4 good qulaity CDRs from two different brands/batches.
I also happen to have the a second drive in my computer (not RAID) dedicated to backups and quick recovery. Then there's also an external Firewire portable HDD that is another copy of the backup. I say you can never have too many backups.
This is how I backup my precious photos. For regular data, all of it fits on one CDR so at least once every month I write a full backup to a CDR. The CDR has got to last at one month right?
As for MP3s... that's what P2P is for.. distributed backups.
The test I do now (which I learned the hard way from early burning experiences) is to hold the cd-r up to the light. If you can see through it, chances are it won't last. The cheapo bulk disks that have nothing but a silver top are very likely to be the first to flake on you.
Also, keep your burned discs out of direct sunlight and excessive heat, both which will cause the top foil layer to come off. Even quality media will give out on you after exposure to the elements.
If you can't beat them, arrange to have them beaten. -George Carlin
which is a completely ridiculous notion. Well no, let's not be so aggressive, it's not COMPLETELY ridiculous. But if that reasoning was all true, if the laser had the time to burn a pit normally at 1x, then that time would be divided by N at Nx speed (well not exactly, but that's beyond my scope), and the pit would be N times "weaker".
So of course, the power of the laser is increased to palliate this effect.
So in an perfect world, the laser power would be increased 32 times when you increased the speed 32 times, thus making the same pits as if you burned in 1x.
Now this is only taking into account laser power when burning at higher speeds. Thing is, there can be lots of other problems when burning at higher speed, any minuscule glitch in laser power, rotation speed, laser position, anything can cause a problem. Of course most problems are corrected, and those that pass aren't fatal. But with age, the organic compound on which your data is written deteriorates, as any organic compound would, and the errors get worse.
Misleading titles? Inflammatory blurbs? Keep in mind that Slashdot is a tabloid.
There is one thing that unites us all- our love of pornography.
What a silly thing to say. Taking it seriously for a moment - There are lots of people who disapprove of pornography, for one reason or another. The political left (feminism) considers it exploitative, the political right (conservative religious) consider it amoral, and women (even geek women) don't tend to be consumers of pornography. Since Slashdot certainly has its share of political left, right, and women, it's easy to see that no one thing will EVER unite ALL Slashdot readers.
That being said, posts about pornography don't get modded up to +5 Funny more than any other running joke. It hardly takes the entire Slashdot community to moderate a post to +5 Funny, and it doesn't happen any more often than your obligatory Simpsons quote, or CowboyNeal reference, or beowolf cluster, etc.
Experts agree: everything is fine.
Using Grease to seal a CD-R?
You mean encoding selections from the 1978 John Travolta and Olivia Newton John movie on the outter tracks of the disc? Brilliant! Even O2 won't react with John Travolta.
As far as removing Grease, the Church of Scientology can remove anything it wants. Its the perfec solution!
Troll Like a Champion Today
Does it matter? Yes. Is slower always better? No.
Rather than re-hash this, please see:
In the CD-Recordable FAQ.Quick summary: higher speeds require a different "write strategy" than slower speeds. Different media formulations are optimized for a particular write strategy, so writing slower than the optimal speed can actually produce inferior results.
The choice of media and recording hardware has to be taken into consideration. In any event, this has relatively little to do with disc deterioration. A disc that's better to begin with won't show the effects of physical deterioration as soon, but if the top lacquer coat isn't as close to air-tight as materials allow, it doesn't matter how you write the disc.
It is absolutely true. It becomes increasingly difficult to create well-formed pits at higher rotation speeds due to the more difficult timing tolerances. Also, it is easier to get predictable burn results at a lower laser power setting.
CD-RWs are extremely photosensitive.
The biggest benefit is that it cuts WAY down on the number of +5 posts, so you can get straight to the key comments if that's all you want. It's cool when the home page says "24 of 215 comments" but when you click in the Funny modifier filters half of them out and you end up only having to plow through 12 :)
One simple rule for its versus it's
Same here. I've got disks from when I got my first CDR. Was just using one the other day. My guess is the failures are if you use unbranded disks on an unbranded drive. I had one CDR drive that was AWFUL. You'd burn a disk, eject, put it back, and it would think it was an audio CD. Terrible drive. Disks burnt on that drive are EXTREMELY flaky.
Actually, thinking about it, I do have a couple of disks that are tough to read, but the fact is they've been like that from day one.
-
MAM-E Gold Ultra, about Eur. 1.15 each.
-
Mitsui Gold Ultra, about $1.60 each.
Kodak used to be in this market, but seems to have exited it.The key here seems to be dye type. Phthalocyanine has slower writing speeds but longer storage life; Cyanine has higher writing speeds but much shorter storage life. The "archival grade" CDs also have gold reflecting layers and a tougher substrate.
There are also "Medical grade" CD-R blanks, but they're essentially the same as the archival ones.
There are programs which will read the ATIP information from a blank, telling you what the manufacturer, max writing speed, and dye type is.
Mitsui is currently the only company making archival quality CD-R media with a phthalocyanine dye layer and a gold reflective layer.
All archival quality CD-R's use phthalocyanine, it is the only stabilized dye known to last more than 100 years. Gold is the absolute best reflective layer available because it is almost completely non-reactive.
The combination of those two is the only way to get a true 200 year archival life CD-R. They aren't "cheap", usually less than a dollar each but 85 cents in a 100 pack isn't unusual. Try this google search. The second link is a place selling 100 packs for $82. That's 82 cents a piece for a CD-R that should last until the year 2200.
If you're willing to live with slightly less... I managed to pick up a pack of Fuji CD-Rs with a phthalocyanine dye layer and aluminum reflective layer. Fuji seems to think they will last 100 years, but I have my doubts. Still the #1 reason CD-Rs fail is the dye layer, not the reflective layer.
Education is a better safeguard of liberty than a standing army.
Edward Everett (1794 - 1865)
According to this ancient Seybold report, Dataglyphs can achieve densities of a kilobyte per square inch.
DataGlyphs were featured in this /. article about chess playing scanners.
Bleh!
MAM-E Gold Ultra CD-Rs are guaranteed by the manufacturer to last for at least 200 years.
Fuji is made by Taiyo Yuden. ... TY is also making some Memorex
Both Fuji and Memorex have TY and non-TY discs. But you can, as you say, check the packaging for the country of origin. As far as 50- and 100-spindles go, every "Made in Japan" I've bought from these two brands has been TY, as reported by CDR Identifier.
--
Dum de dum.
Freedom is not the license to do what we like, it is the power to do what we ought.
These CDs WERE NOT WRITTEN TO. They were stored on the original spindles for 20 months and then HARDWARE ANALYSED. The CDs were all completely blank.
[insert witty comment here]
From a little googling, I now see that they signed a Memorandum of Understanding with the Rainforest Action Network promising to change their ecologically unfriendly corporate practices. Here is the link:
http://www.ranamuck.org/news7.01mitsi.htm
Provided the humungous Mitsubishi zaibatsu is living up to their promises, I have no problems now recommending Mitsubishi Chemical CD-Rs. Everything I said about TY goes double for their disks.
The reasons why TY and Mitsubishi CD-R blanks are so good and so compatible are the fact they use a much darker dye than the Taiwanese manufacturers do. Yamaha suggested the use of Mitsubishi Chemical CD-Rs with their "Disc T@2"-equipped burners because the graphics would show up better. They are a better choice for maximum compatibility for the same reason they are a better choice for "Disc T@2". The more visible the dye layer is to the naked eye, the more visible the dye layer is to a CD-ROM or CD player's laser.
I wish I could back my assertions up with a whole list of studies, but I am basically speaking from several years of my own experience with CD-R blanks. I don't see as many CD-Rs made by TY going bad as no-name Taiwanese crap does.
Knowledge is power. Knowledge shared is power multiplied.
I left my CDR's out for about 3 weeks and
check out the results:
http://www.techfreakz.org/cdruv/
These are name brand CDR's exposed to the
sun for only an hour or two each day.
(mod this up guys, people need to be warned).
I read that burning cd's while wearing a tinfoil hat decreases chances of errors.....
Selling software wont make you money, selling a service will.
a while back http://www.cdmediaworld.com/ had an article explaining how there were something like 256 different brands of CD media, but only something like 16 different manufacturers of the actual media.
Taiyo Yuden were reckoned to be the best manufacturer. they make discs for lots of different manufacturers, but you don't know 'til you get home and get yr CD writing software to read the code off the disc and tell you who the manufacturer is, bcos it aint gonna tell you on the packet. and different sub models of disc can be made by different manufacturers.
I think TDK even had the same models, with some made by Ritek (the worst quality) and some made by Taiyo Yuden. there was a court case against them for this.
I buy a single TDK disc, take it home and check it, and if its made by Taiyo Yuden I go back and buy loads of that same model disc, and have been able to get the people in the shop to say they'd take the discs back if they weren't Taiyo Yuden (a large consumer-space chain in the UK, I shan't name them incase they read this and stop being so remarkeably fair)
Same here, I have CD-R's from my Ricoh CDRW (the first one on the market) that are now 6 1/2 years old and all of them that aren't scratched to hell are still readable. I wonder if this isn't indicitive of a falloff in quality of blanks. Back then blank CDR's were over a buck a piece and to get ones that would read in most normal cdrom or audio players you had to pay around $4-5 a piece, now you can get CD-R's for around 5 cents a piece. Obviously scales of economy have dropped the price but I'm wondering if cheapening of materials has not also been a big part of it.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Close, but actually it is inducing a color change in an organic dye. This dye is either green (unburned) or clear (burned), and is sandwiched between a reflective and a non-reflective layer.
-- You are in a maze of little, twisty passages, all different... --
This is the biggest problem with the CD-R market. There's no long-range consistency in the formulation of the discs. Even within the same line, by the same manufacturer, there will be formulation changes, even dye changes. Outside of the brands that make their own discs, it's even worse - you're at the whim of whoever the lowest cost producer was (ie, Sony's discs are outsourced that way.)
:P
I used to buy only TDK. Then I had to switch to Verbatim when TDK started getting cheap on me. Now I'm using Mitsui media. When I started burning CDs on my 2x burner (I now have a pair of 8x burners and a Pioneer DVR-105) I was reasonably confident my data could last up to 10 years (I burned 3 copies, on different brands of CDRs.) Nowadays I haven't a clue as to whether my data will last the year
Time to make a fourth copy of my data and put it on a removable HD...
IsoBuster
AT&ROFLMAO
The other poster is correct. While we did not examine CD-RW, as they didn't really exist at the time, and also violated a rule for archiving for the group we were doing work for, which is that you can change them undetectably, I would imagine they suffer from the same problem as other mediums. Panasonic's phase-change designs were excellent, and substantially more stable than MO-RW, but in the end, they were VERY sensitive to UV, which is why they were in cases that had shutters that had interlocks. CD-RWs don't have this.
These CDs WERE NOT WRITTEN TO
And here is the key.
I've seen other tests where CD-Rs can't be written reliably after sitting around blank for a few years or artifically "flash aged" using elevated heat &c.
That matters to me a bit, but what's much more important is how reliable the data can be read after *being written*, then stored for years.
I use Kodak pseudo-golds (they don't make the real gold on gold ultima anymore) for anything I care about. The discs should be good, but they are also actually made by Kodak. No problems with the manufacturer changing & the brand remaining the same. No research on who's selling the best Taiyo Yudens this week needed.
Oh, shit! Good things never last. Well, the folks I bought my last batch of Kodak's from have a replacement: Mitsui Golds
I don't abuse my "archival" discs, so I don't care much about scratch-resistance, which is all some "life" discs offer. I care about bit rot.
the point is, it's not a pit/hole, but rather a physical change (chemical, phase, color--whatever) in the medium (an organic dye). So it's not a function of how deep the hole is, as the theory of "slower burning = deeper hole" so requires.
Stupid people make stupid things profitable.
I've talked to companies which make these types of tools and asked the same question. The simple answer is that a normal CDRom is just not built for advanced testing. Testing drives have specific hardware to detect errors that a normal CD can't. Naturally these errors don't influence the percieved quality of the product, since they can't be measured by standard hardware. However it can demonstrate problems with the manufacturing process.
The two main CD-R companies are Ricoh, in Taiwan, and Taiyo Yuden in Japan. Now which company do you suppose makes the better discs? Check the "made in, hecho... etc." label before you buy discs. "Made in Japan" discs are head and shoulders above Ricoh discs. Not only do they have higher standards in Japan, they also use higher-quality dye. After that the main thing to look for is a nice, non peeling top. I recommend Fuji, Mitsui, HP, and Kodak discs if you are looking for a CD-R that will keep your data safe. I've burned thousands of CD-Rs over the last 5+ years, and not a single one of my archive discs have ever "gone bad", or flaked out on me. Those archive discs are mostly TDKs from back when they were made by TY, and Fujis.
Anti-social? My code is just platform-specific.
i *had* several panasonic phase change drives.
the media and technology is shit. period. it died off for good reason.
every single one of the discs died within a year with unrecoverable errors under even light occasional use.
even the crappiest CDR/RW technology I have seen is light years beyond that panasonic phase change crap.
ps i still have the drive and dead media sitting around, if anyone wants to buy it cheap...
You're joking, right? I hope you are. But if you aren't, then: If something catastrophic were to happen at my friend's house, then obviously I would still have all of my original data at home. Then I would leave a fresh backup at his new place, after helping him get settled in there.
Leaving a CD-R at a friend's house is free. Fireproof safes are not. In addition, what if the burglars were to find and steal that safe, hoping to be able to break it open at their leisure and get the valuables inside? Then you would be wishing you had a current backup off-site.
It actually depends on the drive. I remember back in the day when Adaptec Easy CD Creator put out a regular newsletter and discussed this. The older drives would produce less crc errors at slow speeds. Newer high speed drives will do better at high speeds because that is what they are designed for. The higher speed drives are only calibrated at the top speed burns.
BTW, I had some audio cds stored in my car that lasted over 5 years. I finally threw 'em out because they started skipping on some tracks. I still have some data backup discs from the same time perios and they still work fine. Of course they are stored in a less environmentally extreme storage- in the cabinet above my desk.
Just a Tuna in the Sea of Life
> Since Slashdot certainly has its share of political left, right, and women, it's easy to see that no one thing will EVER unite ALL Slashdot readers.
Sure there is. Our love of bandwidth.
if the answer isn't violence, neither is your silence / freedom of expression doesn't make it alright