Burn ring size on completed discs question

[DarrylRowan]

Hi,

I'm burning 3 files with different methods using IMGBurn.

First, I am creating an image with the files, using "Create image file from files/folders" and then burning it to disc, using "Write image file to disc".
Secondly, I am just adding the 3 files to a new "Write files/folders to disc" and then proceeding to the burning it to disc.

All situations are to finalize DVD.

I have noticed that the discs once complete, have different size burn rings. The one that is using "Write image file to disc option" is 12mm thick and the one with the 3 individual files burned using "Write files/folders to disc option" is 5mm thick.

Why does this happen? What extra stuff is it burning to the disc? The image file is the same size as the 3 files collectively.

Thanks,

Darryl

Edited March 9, 2023 by DarrylRowan

[dbminter]

Well, the image file size should not be the same size as the 3 input files.  The image file format is a container and therefore will be larger than its contents because of overhead, file system metadata, etc.  So, when you burn an image size to a disc, there will be "more" burnt to it because it contains this various metadata overhead.

 

I can't comment on the Write files/folders to disc option as I've only ever used it to test things other have reported problems with.  But I would guess that it dispenses with the overhead metadata associated with a container file as no image file is written first.

 

Plus, it depends on the data being written.  For instance, a DVD Video should have theoretically different burn sizes because it uses a specific file system format type and associated metadata for DVD player playback compatibility.

[DarrylRowan]

Hi and thanks for your reply.

 

Is there a minimum burn ring (size on disk) for ISO files?

 

For example, if I burn 250MB, 10MB, 1MB, or 1GB, are they going to have the same burn ring if I burn an image?

Edited March 9, 2023 by DarrylRowan

[DarrylRowan]

Another example is with Clonezilla. The file size is 300MB and it is an ISO (Image) file.

 

When I burn it to DVD at a individual data file, it'll show a burn ring of 3mm thick. However, when I burn the file as an Image to DVD, the burn ring will be 13mm thick.

[dbminter]

The more data you burn to a disc, the larger the extended area of the burn ring.  So, 250 MB will have a smaller area than 1 GB.  However, if you're burning a double layer DVD Video, those employ what is known as padding.  So, their ring areas may not necessarily be indicative of the actual size on the disc.  For instance, I once burned a DVD VIdeo that was just a few MB larger than the size of a DVD-5.  Yet, nearly the entire DVD+R DL burn area was used.

[DarrylRowan]

I could really go either way. Create an IMAGE file from files and then burn it or go Files direct to DVD burn.

The reason I wanted to do the IMAGE file option is to be able to get a SHA256 hash from the ISO I created.

I was kinda concerned that the extra burn area was "junk" padding and could be something malicious. Who knows.. just my paranoid mind playing on me. Like if I was to say, that 1/8 of the disc was used (burnt) for the files and 2/3 of the disc was used (burnt) for the ISO with the same files, it creates concern.

I think you may have answered my question though. It probably is padding and nothing more.

 

 

Edited March 9, 2023 by DarrylRowan

[dbminter]

It's analogous to a file on an HDD.  It may be 1 MB, but it actually takes up slightly larger than 1 MB of space because of various metadata overhead.