Trouble transferring data between external drives - shrinking file size?

Hopefully you get someone to answer here.

I was curious about this, so I started googling. These are my results.

http://support.apple.com/kb/HT2355

Journaling doesn’t seem to have any meta-data. This is probably what you were thinking was being stripped from each file in the transfers. It’s possible that it is meta data of some sort, but I don’t believe the journaling is the cause.

Here is someone who agrees with me, read their response at the very bottom of the page.

“Too late to include in my last reply, I noticed your comment about needing to copy the files to an unjournaled partition somewhere. Journalling doesn’t have any effect on file size or fragmentation—it is essentially a method of recording pending file changes so that should that process be interrupted, the file system knows what files might be out-of-date without going through the entire file system.”

The original drive my be fragmented. When the files are written to the new drive, they will be written with no to less fragmentation.

I recommend de-fragmenting the original drive, then see if the content sizes are closer.

also, if they are different file systems (FAT32, NTFS, ...) there might be a slight difference maybe… I don’t know.

Cheers ,how do I check if they are different file systems?

Also I have attempted defragging on a mac before with little success, but will try it.
Was curious if that might be the reason especially because the drive is so full.

if your on pc you can open ‘my computer’ right click on each of the drives and go to ‘poperties’. On the window it will say “File system: NTFS”, “File system: FAT32”, or something else. I don’t really know if that will make to much of a difference. Does anyone else here know perchance?

Macs don’t use NTFS or FAT32.

Thought that might be the case.
But could it really just be the fragmented files?

I just can not see any other easy explanation.