What I really need to do is check my existing DVDs for errors before I make backups and then check those backups for integrity. I've been told that the DVDInfroPro CRC Test is best. But then there's Nero CD Speed. It has two tests I've used: DISK QUALITY and SCAN DISK. Scan Disk has two tests... SURFACE and FILE TEST.

I thought I could use these tests instead of DVDInfor until I tested a refinished disk that read almost entirely red... ie "unreadable"... yet the disk played fine in my CD drive... enough so to make a successful backup.

The original disk also got a terrible test score of 18 in the DISK QUALITY test.... yet completely passes the DVD INFO PRO CRC test.

So is CD DVD SPEED the wrong tool for testing whether DVD is readable or not? Is it the wrong tool for testing whether a burn is successful or that the media was not defective?

If no, just what is CD Speed good for?

Or should I stick with the CRC test in DVD Info even if I have to jump though hoops because it constantly expires days before a new version is available?

The new version is available now. LOL.

As for your question;

DVDInfoPro has the ability to read back the physical block integrity of the media, as well as the surface "structure" or physical layer as well. When the light is "green", it means surface is clean, as is the CRC error correction. When it is white, it means there is physical block damage and the PUH attempted a re-read (which was subsequently successful). When red, it is a CRC hash FAIL. The tool has these intermediate report methods so that users can understand EVERYTHING about the CRC check, at a glance.

Helps?

Cryptomorph,

I sent you an email on how to properly behave on the board, please read it, and heed it.

(in reply to zebra)

Hi,

To be very basic about this, the difference between disk quality and CRC checking is that, the quality check is giving you some indication of how much error correction will be needed to correct a block with errors, the more errors the more likely the disc will get CRC errors along its life span. CRC error checking is telling you that the current disc, in the current drive is readable with all errors corrected, or that some errors needed a second or third shot at correction, or that they were not correctable.

cheers
nicw

(in reply to MP3Mogul)