lower than expected level of compression

[guest]

Hello, noob question here please! I have the trial version of R-Drive Image (great program, by the way!) and have made an image of my .mp3 music and (mostly .mp4) video files using the 'backup files' function. The drive is an internal hard drive formatted to NTFS. While I wasn't expecting a huge reduction in file size due to the already compressed nature of the files, it only reduced the total size from 513gb to 500gb, even when the compression slider is set all the way to the right. I was wondering if this is normal or if in any way I could reduce the image size further - maybe by changing the image format or file system of the drive? Or any other setting? Thanks very much.

[Alt]

it only reduced the total size from 513gb to 500gb, even when the compression slider is set all the way to the right.

It's quite a good reduction for highly compressed files. Further attempts to increase compression my result in increased file size.

[guest]

it only reduced the total size from 513gb to 500gb, even when the compression slider is set all the way to the right.

It's quite a good reduction for highly compressed files. Further attempts to increase compression my result in increased file size.

Thanks for your reply. Am glad it's a good reduction. I won't try to increase compression further as you recommend.

I will also be backing up an 8tb drive which contains less compressed files, so maybe a larger reduction will be possible with those.

Thanks again!