Big Prob

I have burned a DVD, I noticed after burning a big black smeary mark on the back the same colour as the unburned bit on the outer edge.
I done a surface scan with CD/DVD speed and it had no problems.
Then done the transfer rate test and the lines went right down to the bottom where the mark was on the cd.
I thought that if the surface scan displayed the dvd being 100% the files have 100% of their data with no loss and you can copy them back.

Looking at the back of the dvd and the transfer rate results it doesnt look like i would have 100% of the data on the disc.

Can it still display it really bad in the transfer test but then if i play the file back it will still be 100% ok?

yes it can display a bad transfer rate graph and still read the files ok (at least for now), the bad graph probably means its re-reading parts of the disc (not good if you want a disc that will be readable for a long time).

I would worry about this burn and I would trash it no matter what any testing showed. There is always something that can goof it up. I can imagine a sector that would be good but that would be hard to read or have bad data, so what you have seen is not mutually exclusive.

yep, id reburn the data onto another dvd and then chuck the old disc in the bin.

Thanks very much.

I’ve also noticed that if i leave a TY disc with the burned side facing up all night in no cd case this condensation like looking dust builds up on the disc, when i go to rub it off it wont come off.
It can only be seen when a light is shining on the disc.
The disc that was on the top of the pack was the worst affected by it.
It looks like dust thats been burned into the disc, but its not because it was there before i burned it, but could only be seen round the very outer edge before burned.

What is this stuff?