Hi. Does recoding a DVD always reduce quality even at 100%

I know that you would not perform such an action if you can just copy the disc at it's natural capacity but does the act of recoding reduce quality even if the software you are using states that 100% quality will be retained?

Please explain a little bit more about what you are doing.

Are you just copying DVDs using your computer?

If so, then this depends on the method you use to backup the DVDs.

Generally, if you are encoding/re-encoding media, you will lose a little bit of information each time it is re-encoded (even if it is at "100%").

I was archiving a disc in Nero 9 but shrinking it to DVD5 size; it went through the whole process of Analyzing and Recoding the data. It then asked for the blank disc, and, when I placed the blank disc in to the drive, Nero blew up and stopped responding; however, the recoded files remained in the temporary directory.

I thought I could just perform a straight-forward Copy operation and redirect the path to the temporary folder but Nero Copy will only accept a disc from a device drive.

So, I went back in to Nero Recode and picked up where I left off - I selected the directory where the recoded files were and it recalculated the quality. In this case all values were at 100% because the data had already been shrunken to fit a DVD5 disc, but, technically, the data is being recoded again.

That is why I asked, if you take a disc and recode it instead of copying it, even if no quality is being compromized by the software; i.e. the software reports 100% quality retained, does the act of recoding still compromize quality if no shrinking occurs?