A 24.6 GB Blu-Ray Disc image that will not burn to a 25 GB BD-SL

[fronn]

When marketing departments say 25GB, 100GB, 500GB, etc. They are counting bytes differently than the rest of us, oddly enough. They are saying 1000 bytes = 1KB, 1000KB = 1MB, 1000MB = 1GB. In reality it's 1024B/KB/MB to KB/MB/GB.

the 25GB disc can only hold 25,000,000,000 bytes (give or take, before file system related things like the TOC and stuff)... a true 25GB disc is 26,843,545,600 Bytes.

A single layer BD disc is only going to hold a bit over 23GB. The file is simply too big.

It's the same reason a formatted hard drive drive in your computer is always less than the size stated on the box... it's not because formatting eats space, it's because the PC is reporting the size accurately and the box, well, isn't.