What is the capacity of a BD-R disk really?

Tom Horsley horsley1953 at gmail.com
Sat Nov 26 16:26:43 UTC 2011


On Sat, 26 Nov 2011 16:09:25 +0000 (UTC)
Andre Robatino wrote:

> Using command-line tools, can you actually create an ISO of size <= 25 GB which
> can't be burned to your media?

I haven't tried creating an ISO file because it takes so long to do that
then just as long to burn it, but I may go that route the next time I
accumulate enough data just to see what the numbers are.

In theory an ISO image less than 25,025,314,816 bytes should fit
(if the FAQ page I found is accurate).

> I would hope that the advertised capacity doesn't
> include unusable overhead, otherwise the number is meaningless.

It is close to meaningless anyway when none of the tools
work right with whatever algorithms they use :-).


More information about the users mailing list