try a non apple gauge, like this one: http://www.daisydiskapp.com/ ? looks wacky though.
Apple Event: May 7th at 7 am PT
I can confirm that DaisyDisk works really well and actually has quite an intuitive UI.
Thanks for the tip.
My main reason for posting this here, is because I don't want to submit feedback to Apple without some confirmation that there is a problem (ie. not finger trouble on my part). I'd be quite happy with Disk Utility and Activity Monitor, but need to trust the information they give.
I don't think this forum is well constructed for discussing particular issues. There is a need to separate disgruntled rants from specific constructive dialogue😎 and god knows, Apple need to eliminate these bugs fast or they'll get knocked off their pedestal.
it really is an innovative approach to disk cleaning...
You are missing the point, I am quite happy with the Apple interface and try to avoid third party software.
What I want to do is draw attention to a bug that is taking away my trust in the system. Activity Monitor and Disk Utility are giving false information!
I've just found more information at About this Mac>More Info>Storage
It seems that the deleted 50Gb is now in the "Backup" sector of the bar chart, unless it is this space now being used by Time Machine Snapshots. There is still a discrepancy between Get Info, Disk Utility and Activity Monitor.
Finding out how much disk space you actually have may not be so easy now Snapshots uses any free space for itself. I submitted a Bug Report.
I have turned off the Snapshot option in Time Machine Preferences and the numbers now agree.
See the following thread
https://discussions.apple.com/thread/3204935?answerId=15732534022#15732534022
Disk space information