DVD size question

[sparky]

Can anyone tell me what is happeining here.............

I created some back up files with a disk imaging tool. I formatted all of my DVD-RW's under windows vista, just single layer ones, 4.7gb. Then I tried to drag and drop the files to the dvd-rw, but Vista won't have it. It says there is not enough space and I need another 130mb.

I then run Nero, create a new data dvd, and add the backup file. When I hit burn, it says that there is already something on the disk, quick formats it, then burns the disk with no problem and the file is complete.

So what is Vista leaving or putting on the DVD when you fomat under the operating system? Anyone any ideas?...............Keith.

[Rik]

At a guess, Keith, it's putting down a filing system so that the disk can be used in RW mode. Nero is burning it as an RO disk from the sound of it.

[talos2]

So what is Vista leaving or putting on the DVD when you fomat under the operating system? Anyone any ideas?...............Keith.

Probably a hissy fit.           It'll work ok next time (probably)

[sparky]

No hissy fit....

All the DVD's I tried did the same thing......I think Rik is probably right about the filing system......sounds a likely reason to me. Especially as I burned the DVD as a NON-Multisession disk as well.

[drummer]

The default capacity of formatted DVD-RW disks is (I think) 4,70Gb.  The trick is to not format and let your burning software think that it's just a normal DVD-R.

Formatting RW disks is only necessary if you need to drag and drop files to them (AKA, packet-writing) and that really isn't a good idea because RW disks fail with alarming regularity.

[sparky]

Hi Drummer,

What do you mean by "RW disks fail with alarming regularity"..........

Do you mean during the use that they would get if being used to drag/drop files or in general........

ie. Are you saying it's not a good idea to keep a backup on DVD-RW disks ??
or are they OK once they have been written to ??

Cheers.

[Rik]

They do fail in regular use as backup media, Sparky - they only have a limited number of write cycles due to the dyes degrading. Although I do use them for backup, they are the 'last resort' medium, I've already written the data to one internal and two external HDs first.

[talos2]

They do fail in regular use as backup media, Sparky - they only have a limited number of write cycles due to the dyes degrading. Although I do use them for backup, they are the 'last resort' medium, I've already written the data to one internal and two external HDs first.

That would explain why most of my saved and backup files on RW's wont read on my new system, thanks Rick it looks like I've a lot of work to do

[Rik]

Do they read on the old system, Bob? It could be a tracking issue with the different drive.

[talos2]

Some wont read on new or old system, problem is I didnt find out until I tried to put the files on the new system, I put it down to damage caused in the house move, but as you say if the RW degrade that would explain it.

[Odos]

Another point to bear in mind is the actual size of the disks. I know most say 4.7 gig BUT that is in metric measurement whilst in computer terms they are actually 4.38 because the basic multiplication factor is 1024, based on hexadecimal which computers use, and not 1000 which is decimal that we people use.

[drummer]

Another point to bear in mind is the actual size of the disks. I know most say 4.7 gig BUT that is in metric measurement whilst in computer terms they are actually 4.38...

Oops, that's what I was trying to say...

And to sparky, yes RW disks are very unreliable for the reasons Rik has described.  I only use them now to verify that the project I'm working on plays on a domestic DVD player.  After about ten sessions, the disk becomes either unreadable or I can't write to it.

[Lance]

I think the best method of personal backup at the moment is either a external hard disk or a couple of USB memory sticks.