Optimize photos in MAC OS

[rockycmt]

My photos lib is quite large. 729G. This is years of photos in my collection. I am trying to offload some of this storage off my MAC. I learned of the optimize Mac Storage option. So 2 days ago I turned this on. I expected to see the OS start to replace some photos in my lib with low res photos thus shrinking my lib size. Well it has been two days and I see no reduction. What should be my expectation here?

Let me also add I am approaching a full 1T disk. 994.66/1T
TY

 

[Mike Boreham]

My photos lib is quite large. 729G. This is years of photos in my collection. I am trying to offload some of this storage off my MAC. I learned of the optimize Mac Storage option. So 2 days ago I turned this on. I expected to see the OS start to replace some photos in my lib with low res photos thus shrinking my lib size. Well it has been two days and I see no reduction. What should be my expectation here?

TY

I have had similar experience.

The reality is that we have very little control over what happens. The key words are in Photos > Settings:

"Optimise Mac Storage
If your Mac is low on space, full-resolution photos and videos are
automatically replaced with smaller, device-sized versions. Full-resolution
versions can be downloaded from iCloud at any time".

Turning on Optimise is simply giving macOS permission to replace full resolution photos and videos if your Mac is low on space. If your Mac is not low on space it will keep full size ones. Apple doesn't say what it thinks is "low on space".

A workaround if you want to force a smaller Optimised library is to put the library on a separate APFS space sharing volume in the same internal container , and set the quota to say 400GB. Then delete your current 700GB library and create a new Optimised one on the 400GB quota volume. Because of the quota the library will not be able to grow above 400GB, in fact less because it will keep some headroom. Because of APFS space sharing it won't use any more space overall and you will gain 300GB+ free space.

 

[PotentPeas]

If you "Get info" on your main drive, does it show any "purgeable" space?
I.e. mine says:
Available: 1.95 TB (591.8 GB purgeable)

The "purgeable" space includes space that is "used", but that is used by data that macOS will start deleting if the disk runs out of space. You don't need to manually "purge" this, it happens automatically if the disk fills up.

I'm not sure if your photo library is included in this but it wouldn't surprise me if it is. Apple's general strategy is to keep photos/videos that are stored locally (either because they were stored there before you turned on "optimize storage", or because you manually opened up whatever specific photo video), and only offload them if the disk is really full or close to full. Works the same way on iPhone.

 

[Bazza1]

On a different tack -
I'm not sure where you keep your photos - I don't use Apple's Photos app for anything but the occasional down and dirty editing (my pics instead living in a manually created folder within my user folder), preferring to keep away from any of Apple's proprietary storage or optimization. And, for the most part, I reduce the actual dimensions of my photos (usually with Preview) before saving them there, as well.
As for optimization of all else, I've been trying out the free ImageOptim app (https://imageoptim.com/mac) recently, reducing the bumpf of individual pics or batches of them. The end result replaces the original in location - but puts the original in Trash lest you have a change of heart.

Just a option...

 

[ignatius345]

My photos lib is quite large. 729G. This is years of photos in my collection. I am trying to offload some of this storage off my MAC. I learned of the optimize Mac Storage option. So 2 days ago I turned this on. I expected to see the OS start to replace some photos in my lib with low res photos thus shrinking my lib size. Well it has been two days and I see no reduction. What should be my expectation here?

Let me also add I am approaching a full 1T disk. 994.66/1T
TY

I’ve got just over 500 GB of photos and videos in Photos. Highly recommend buying an external and moving your .photoslibrary database onto that. You’d instantly free up your entire internal drive and not have to fret about what iCloud is or isn’t purging. In fact, you could just opt to flip on "Download Originals to this Mac” and potentially save $ on your cloud storage.

If you do this, just make sure your external drive is getting backed up along with your other stuff.