Dual layer DVD probs :(

I copied a load of pics to dual layer DVD's (verbatim -r's using nero6), and the transfers went OK (i.e. no errors, data verified). I've now gone back to look at the files (mostly cr2's, some jpg's) and although I can see the files in the folders, copy them etc, the files towards the end of the disc are unuseable. I presume these are the files on the second layer (disc is about full, and they start to fail about half way through).
Anyone any ideas what has happened? Luckily the images I've lost aren't very important (2 out of three discs have done this, the third is ok and has important images on it - phew!)
Any ideas if I can recover them?

I never trusted the dual layer media for backup purpose since it's a new technology and even with regular dvd-r +r, Most of the discs are not near archival quality. So I prefer to have a second external hard disc to backup my files...

You could see if you can check your disc in a another dvd drive. But if the disc is bad, then your out of luck. Check the integrity of the disc with a utility in Nero

I have an HP Pavilion that would copy files and read them for a while but then stopped. Eventually the drive stopped reading from all disks. I know it's not the same as your problem but I did have HP replace the DVD drive under warranty and everything is working great now. Maybe a drive problem. Have you tried reading from another computer?

Try Verbatim +R DLs. Those are the only DLs that are recommended by those who know the difference with DVD media.

Dew wrote in post #830948
I copied a load of pics to dual layer DVD's (verbatim -r's using nero6), and the transfers went OK (i.e. no errors, data verified). I've now gone back to look at the files (mostly cr2's, some jpg's) and although I can see the files in the folders, copy them etc, the files towards the end of the disc are unuseable. I presume these are the files on the second layer (disc is about full, and they start to fail about half way through).
Anyone any ideas what has happened? Luckily the images I've lost aren't very important (2 out of three discs have done this, the third is ok and has important images on it - phew!)
Any ideas if I can recover them?

Long shot but going by the fact that Nero could verify the written data can you (1) use Nero to extract the disk image as an ISO file and then (2) use something like Ultra ISO to mount the extracted ISO and get your files back.

For backup, I prefer a portable hard drive. The one I like the most is a family by SmartDisk called the FireLite.

Their 80GB version sells for about $99 (US) at Best Buy, and their 120GB version sells for about $130 (US). Both of these units are about the size of a typical PDA and connect via USB-2.

They are very portable and operate at a very acceptable speed for me.

Raphael Emond wrote in post #831642
I never trusted the dual layer media for backup purpose since it's a new technology and even with regular dvd-r +r, Most of the discs are not near archival quality. So I prefer to have a second external hard disc to backup my files...

I have many DVD's both single and dual layer and have sofar not experienced any problems. I always test the DVD's on a difference pc to make sure they are good.

You might be out of luck if your drive is good (implying that the disc is bad). DVDs use widely varying technology on the layer that is written to.
I have started using Taiyo Yuden DVDs. I have had flawless performance so far as many here have.

You can not test a DVD by just trying to read back the data. That would only detect fatal errors - big scratches on the disk, or miss-registrations because you hit the computer while it was burning the disk.

What you want is a DVD recorder that supports collection of bit-error information. Then you can test different media and check which media works best with the specific recorder.

A DVD contains a bit of redundancy in the information, i..e each sector can contain a number of bit errors without a problem reading the data. However, you want a combination of burner and media that makes as good copies as possible, so that you haven't "consumed" a lot of the redundancy information immediately. The verify step in Nero does not know how much of the redundancy info that was required during the verify pass.

A second requirement is that a single copy (on DVD or external HDD) is not a backup. Besides the on-line copy, you want at least two off-line copies. If CD or DVD, then preferably written on different media using different burner, to avoid incompatibility or ageing problems. Most definitely stored on different physical locations, to avoid loss from fire, burglary, ...