700Mb CD formats as 576Mb

[Paddy]

I have some 700Mb rewritable CDs.

For some reason, Vista (Home Premium) formats these as 576Mb. Where is the
other 124Mb?

They are currently formatted as Live File System. Does that make a
difference? How would I change the format to Mastered?

Thanks in advance.

 

[Gary Mount]

You can only use the Mastered when you write all the files to the disk at
once.
You do not format the disk when you stick in an unformatted disk but instead
choose to burn files to disk.
After you have gathered the files you want to burn to disk, you then click
on the burn disk button and the files get written to the disk.
The Live File System requires overhead that allows you to copy files to the
disk as if it was a USB memory stick or floppy drive, and that part of the
reason that you miss out on about 124MB.

 

[Paddy]

Thank you, Gary, for a clear answer.

So, a Live File System uses approximately 124Mb overhead. Thus, if I want to
revert to the full 700Mb, I need to go back to Mastered.

As the CDs are already formatted as Live File System, how do I go back to
Mastered? When I erase a CD and then copy a set of files to it, it writes the
files immediately, remaining as Live File System. (I'm using Vista Home
Premium.)

Thanks again.

 

[RalfG]

With a regular CDs you cannot and make formatted discs blank again. The
formatting is burned in permanently the same as data would be. You'll have
to use them as they are now. Only CD/DVD-RWs can be erased back to empty
condition.

 

[Paddy]

Thanks for the answer, RalfG.

 

[RalfG]

Don't Format Your CD,
Instead, you have to ERASE the files that are on the disk, to return
the 702mb.
if you format, you will get 576mb.

Formatting CDs is only useful for UDF/drag and drop functionality for
copying files onto them. It's incompatible with music CD format, Video CD,
or other disc mastering formats. As you've already found out the formatting
itself reduces the storage capacity of the disc considerably. Regular CD-R
can be formatted but never erased clean again back to their original
capacity. Once data is written on them, including the formatting, that space
is consumed permanently as deleted files are merely hidden, not removed.
Only CDRW or DVDRW can be erased back to full capacity and reused.