CDR media data recovery

Separate but related issue, I am struggling with a CDR comprised of MP3s which has mysteriously become suddenly unreadable (yes I have taken all the usual physical precautions). I have used CDR-Diagnostic which gave me a 50% hard error rate and 20% soft error rate. I was able to get one album out of 12 onto my hard drive (strangely all complete). The othere come up with CRC error code 23 (using media checker). I would really like to understand what has happened here and how a CDR can go so completely out to lunch?

Does anyone know of a special CD machine that is used to operate outside normal parameters to recover dodgy data?

Can the reading of a CDR alter its lifespan (ie the laser even at low reading power is gradually eroding the contrast in the dye?

I am very concerned about this as I have 100's of CDRs with important stuff, some irreplaceable. If they are going to fade on me unexpectaedly then I have got a mountainous problem ahead of me?

Who was this disc made by?

Try the disc in different drives.

For data recovery on removable storage media like CD-Rs and CD-RWs
you could try BadCopyPro from http://www.jufsoft.com/badcopy/

Good luck!

Other CD-R/RW data-recovery programs are:

1. CD-Check – http://www.elpros.si/CDCheck/ – Freeware!
2. ISO-Buster – http://www.smart-projects.net/isobuster/ – Freeware!
3. CD-R Diagnostic - http://www.cdrom-prod.com/cd-r_diagnostic.html

Hi Guys

the disc ATIP

Device used to read ATIP from

SCSI ID of Device 01:00:00(Aopen CD-RW CRW4048)
SCSI status SCSI good
Data read by CDR identifier.exe

ATIP: 97m 22s 18f
Disc Manufacturer: Seantram Technology Inc.
Reflective layer: Dye (Short strategy; e.g. Phthalocyanine)
Media type: CD-Recordable
Recording Speeds: min. unknown - max. unknown
nominal Capacity: 657.42MB (74m 50s 01f / LBA: 336601)

Media stored 620Mb MP3 music files
age to failure ca 18months
Error rate ca 95% unreadable
Remarks failed suddenly,one week ok next week duff can assemble TOC slowly
can extract one album of 12 files ok, rest have CRC error code 23

I have all those diagnostic progs you mentioned

have also tried other drives


Can reading a disc cause the cyanine dye to fade?

Is it practicable to examine a disc under the microscope? I havent got one. What power would one need?

I am not too concerned about the loss of music files. I can replace the disc but what I want to know is the reason for the sudden almost total failure

A pal of mine is also experiencing the same drop in reliability in his mp3 collection after a year some have become unplayable (he's got 100's)

>>I have all those diagnostic progs you mentioned

Did you have any help with them? If not at all, the reflective and/or dye layer are probably too far gone...

>>Can reading a disc cause the cyanine dye to fade?

I haven't heard of such a phenomenon, but excessive heat could do damage to the dye layer. I doubt that this is possible with the read laser calibration, unless the laser power calibration is seriously broken and the drive keeps on re-reading the same spot over and over again.

Another problem altogether is high speed rotation (52x or faster) of the discs. On some unbalanced discs this can cause cracks and/or peeling, which can result in total data loss.

>>Is it practicable to examine a disc under the microscope? I havent
>>one. What power would one need?

I don't have information on this type of forensic study. I don't know if it would reveal anything useful without lots of heuristic knowledge about broken cd-r discs.

>>A pal of mine is also experiencing the same drop in reliability in his
>>collection after a year some have become unplayable (he's got 100's)

This is more than often the result of using the cheapest (and often very unreliable) media, sometimes in combination with inadequate handling (uv, heat, humidity, abrasion). I'm not blaming you or your friend for these things, but these are quite often major cause in my experience.

regards,
Halcyon

[QUOTE]Originally posted by Halcyon
[B]>>I have all those diagnostic progs you mentioned

Did you have any help with them? If not at all, the reflective and/or dye layer are probably too far gone...

No - this is why I am reporting this problem - and how do you measure the reflective quality of the layer? I want to be able to quanitify this problem






>>Can reading a disc cause the cyanine dye to fade?

I haven't heard of such a phenomenon, but excessive heat could do damage to the dye layer. I doubt that this is possible with the read laser calibration, unless the laser power calibration is seriously broken and the drive keeps on re-reading the same spot over and over again.

The disc has been used in VCD drive (not pc) about 2 dozen times

Another problem altogether is high speed rotation (52x or faster) of the discs. On some unbalanced discs this can cause cracks and/or peeling, which can result in total data loss.

No obvious physical damage

>>Is it practicable to examine a disc under the microscope? I havent
>>one. What power would one need?

I don't have information on this type of forensic study. I don't know if it would reveal anything useful without lots of heuristic knowledge about broken cd-r discs.

>>A pal of mine is also experiencing the same drop in reliability in his
>>collection after a year some have become unplayable (he's got 100's)

This is more than often the result of using the cheapest (and often very unreliable) media, sometimes in combination with inadequate handling (uv, heat, humidity, abrasion). I'm not blaming you or your friend for these things, but these are quite often major cause in my experience.

We get ambient temps here of up to 35C. I daresay that the media was cheap in the first place. If this is the case I want to be able to identify cheap media. It looks the same as a Princo for example. If its that cheap and nasty you can be sure it will find its way onto the market being passed off as a more expensive product. Its a national sport here - counterfeiting

rgds

headcase