Why does mkisofs create such a huge ISO file?

[CHMatt]

I have successfully split a dual layer DVD into two using IfoEdit. I now have two directories with sizes 3.7G and 4.2G

I am attempting to burn the results to single layer (4.7G) DVD.

Both ImgTool on WinXP and DVD Image Utility on Mac (which use mkisofs) create ISO images with size 7.4G when attempting to process the 3.7G folder!

What am I doing wrong? I'm expecting the ISO images to be almost the same size as the folder content.

Also, can I skip the ISO creation and burn the folder content directly to DVD using Finder on Mac? (I understand that the DVD may not play on a DVD player, but I don't really understand why.)

Cheers
Matt

[johns0]

As long as you created a proper authorized folder there's no need to create an iso,just burn the folder using the dvd burn method,not data.

[El Heggunte]

I have successfully split a dual layer DVD into two using IfoEdit. I now have two directories with sizes 3.7G and 4.2G

I am attempting to burn the results to single layer (4.7G) DVD.

Both ImgTool on WinXP and DVD Image Utility on Mac (which use mkisofs) create ISO images with size 7.4G when attempting to process the 3.7G folder!

WILD GUESS:

you forgot to edit some .IFO(s) or/and some .VOB(s)

— so that mkisofs "thinks" the VIDEO_TS folder should fit on a dual-layer disc and then it will pad the .ISO file with zeroes.