One thing that really stuck out to me in the write speed graphs is the dropouts in the speed. The Maxell seemed to be the only one that didn't have them.
Back in the day my company had a regionally-slightly-popular Linux distro. Every couple months we'd burn 500-700 discs. We were small enough that it didn't make sense to mass produce, so we burned them ourselves.
We would occasionally get reports from people of being unable to read the discs, and so we went through ~6 months of investigation, test shipping to relatives, paying our customers to ship the discs back so we could check them.
Eventually I found that while every disc would validate by checksum of the entire disc (part of our burn process), if I tracked the time required to read every block, the discs that people had problems with would tend to have some spikes in the time it took to read some blocks. The drives we were using would read them, sometimes taking an amazingly long time to do so (like 30 minutes instead of 2), but users drives would just fail them.
Eventually I wrote a new validation process that in addition to the checksum used the timing information as well to determin if the disc failed, and at that point our failures in the field basically went to 0.
But, we got really sensitive to vendors of discs. Basically it was Taiyo Yuden or nothing. Some big brands would give us 20% failures to burn, where Taiyo Yuden was <1%.
show comments
LiquidPolymer
I also thought this was a longevity test.
I do love optical media and have a considerable CD, DVD, minidisc, and blu-ray collection. Like a Luddite, I still enjoy burning my own.
I especially like my Superscope disc copier. It completely disregards copy protection and I frequently make a backup of my favorite CDs which I store. Although much of my stock are older blanks (like those listed in this article)I’ll be sad if CD-R disappears from the market.
show comments
Lammy
Great choice with the Pioneer DVR-111. They're my favorite series of drives ever. NEC ND-3500 chipset; Pioneer mechanism.
Pioneer publish the approved media list for their drives but it's not really detailed enough since it only lists by manufacturer while the firmware is operating on manufacturer plus media code: https://www.mfdigital.com/downloads/Pioneer%20111%20approved...
You can potentially get better results by patching your discs into your drive's firmware using MediaCodeSpeedEdit: https://ala42.cdfreaks.com/MCSE/
show comments
Damogran6
I had PILES of CD-R and CD-RW from the turn of the century that are coasters now. Stored in the dry and dark...just absolutely unreadable.
Oddly, the photo CDs I got professionally written were great.
somat
With regards to the first one described the TDK with the UV guard, I am curious as to what that is. My guess is it has more to do with avoiding UV related damage than blocking UV.
I am not sure the authors spectrometer test(which was very cool, avidly reading that series of articles right now) would reveal anything as polycarbonate is naturally quite opaque to uv light.
Fun fact ordinary clear polycarbonate eyeglasses do just as good a job as sun glasses at protecting your eyes from uv.
dmitrygr
This is not, as one might guess from the title, a test of data longevity on disks
show comments
FuriouslyAdrift
I have CD-Rs from decades ago that are fine... but I always used the whatever the Library of Congress used for archival purposes (they were the pricey dual layer gold ones from Verbatim)
show comments
rbanffy
A durability test would be an interesting future article. I need to dig up my old backups and check how readable they are now.
MelodyUwU
CD-Rs are great, especially taiyo yuden
show comments
ksec
I will take this opportunity and ask. Are there any special CD / DVD player where it could better read very old disk?
quantadev
IMO the only way to perfectly protect yourself against Ransomware Attacks is with CD-Rs, because it's something not even hardware can alter. A skilled take over of the root level of a machine can be encrypting everything and you'd never know it, until the day it denies your access, by deleting an encryption key until you pay up to get it back...you hope.
One thing that really stuck out to me in the write speed graphs is the dropouts in the speed. The Maxell seemed to be the only one that didn't have them.
Back in the day my company had a regionally-slightly-popular Linux distro. Every couple months we'd burn 500-700 discs. We were small enough that it didn't make sense to mass produce, so we burned them ourselves.
We would occasionally get reports from people of being unable to read the discs, and so we went through ~6 months of investigation, test shipping to relatives, paying our customers to ship the discs back so we could check them.
Eventually I found that while every disc would validate by checksum of the entire disc (part of our burn process), if I tracked the time required to read every block, the discs that people had problems with would tend to have some spikes in the time it took to read some blocks. The drives we were using would read them, sometimes taking an amazingly long time to do so (like 30 minutes instead of 2), but users drives would just fail them.
Eventually I wrote a new validation process that in addition to the checksum used the timing information as well to determin if the disc failed, and at that point our failures in the field basically went to 0.
But, we got really sensitive to vendors of discs. Basically it was Taiyo Yuden or nothing. Some big brands would give us 20% failures to burn, where Taiyo Yuden was <1%.
I also thought this was a longevity test.
I do love optical media and have a considerable CD, DVD, minidisc, and blu-ray collection. Like a Luddite, I still enjoy burning my own.
I especially like my Superscope disc copier. It completely disregards copy protection and I frequently make a backup of my favorite CDs which I store. Although much of my stock are older blanks (like those listed in this article)I’ll be sad if CD-R disappears from the market.
Great choice with the Pioneer DVR-111. They're my favorite series of drives ever. NEC ND-3500 chipset; Pioneer mechanism.
Pioneer publish the approved media list for their drives but it's not really detailed enough since it only lists by manufacturer while the firmware is operating on manufacturer plus media code: https://www.mfdigital.com/downloads/Pioneer%20111%20approved...
You can potentially get better results by patching your discs into your drive's firmware using MediaCodeSpeedEdit: https://ala42.cdfreaks.com/MCSE/
I had PILES of CD-R and CD-RW from the turn of the century that are coasters now. Stored in the dry and dark...just absolutely unreadable.
Oddly, the photo CDs I got professionally written were great.
With regards to the first one described the TDK with the UV guard, I am curious as to what that is. My guess is it has more to do with avoiding UV related damage than blocking UV.
I am not sure the authors spectrometer test(which was very cool, avidly reading that series of articles right now) would reveal anything as polycarbonate is naturally quite opaque to uv light.
https://en.wikipedia.org/wiki/Polycarbonate#/media/File:Visi... Note how the transmission is dramatically reduced once past violet.
Fun fact ordinary clear polycarbonate eyeglasses do just as good a job as sun glasses at protecting your eyes from uv.
This is not, as one might guess from the title, a test of data longevity on disks
I have CD-Rs from decades ago that are fine... but I always used the whatever the Library of Congress used for archival purposes (they were the pricey dual layer gold ones from Verbatim)
A durability test would be an interesting future article. I need to dig up my old backups and check how readable they are now.
CD-Rs are great, especially taiyo yuden
I will take this opportunity and ask. Are there any special CD / DVD player where it could better read very old disk?
IMO the only way to perfectly protect yourself against Ransomware Attacks is with CD-Rs, because it's something not even hardware can alter. A skilled take over of the root level of a machine can be encrypting everything and you'd never know it, until the day it denies your access, by deleting an encryption key until you pay up to get it back...you hope.
where is he buying these discs?