Why are my photos uploading?

[blackxacto]

I signed out of iCloud on my 17,1 iMac Mojave 10.14.2, I was asked do I want to keep a copy of all kind of things on my iMac. So if I said keep a copy of my iCloud Library Photos on my iMac, if I have room. Does this mean that the entire photo library is RE-UPLOADED to my iCloud account when signing back in? Why isn't it just merged, and any new stuff is uploaded?

It's taking a lot of time to do this, sheet, sheet! Shouldn't there be some dang warning about the consequences of keeping a copy of your photo library on your iMac?

 

[splifingate]

Your Photos Library /is/ your Photos Library (in-so-much as you have previously-uploaded your content, as far as iCloud is concerned)

iCloud is a 'Sync'ronisation Service, and--as such--the Service seeks only to maintain parity between devices you have chosen to "sync" to the Service.

It often seems that said Service is spending your time with 'duplication', but it is really just comparing what is (remotely) "there" with what you have stated should be (locally) "here".

When you elect to keep a copy locally, the next time you sign-on to iCloud, the Service will identify and compare the local with the remote, and synchronise the two.

If you had the resources you sent to iCloud centralised on a local server, fixed disk or ram, the 'sync' would appear virtually instantaneous. But--given the fact of how relatively-narrow the channel which connects us to the "Cloud" is--the degree of time it takes to compare the local/remote resources lends-well to the concept that OS X/iOS 'appears' to replace local with remote.

If that were the case, my iCloud Photo database and my iCloud Desktop/Documents would (in the times when I start-from-scratch) be reduced to holding nothing.

They eventually (given time) reach parity

I advise patience, Brother <smile>

Regards, splifingate

 

[blackxacto]

Your Photos Library /is/ your Photos Library (in-so-much as you have previously-uploaded your content, as far as iCloud is concerned)

iCloud is a 'Sync'ronisation Service, and--as such--the Service seeks only to maintain parity between devices you have chosen to "sync" to the Service.

It often seems that said Service is spending your time with 'duplication', but it is really just comparing what is (remotely) "there" with what you have stated should be (locally) "here".

When you elect to keep a copy locally, the next time you sign-on to iCloud, the Service will identify and compare the local with the remote, and synchronise the two.

If you had the resources you sent to iCloud centralised on a local server, fixed disk or ram, the 'sync' would appear virtually instantaneous. But--given the fact of how relatively-narrow the channel which connects us to the "Cloud" is--the degree of time it takes to compare the local/remote resources lends-well to the concept that OS X/iOS 'appears' to replace local with remote.

If that were the case, my iCloud Photo database and my iCloud Desktop/Documents would (in the times when I start-from-scratch) be reduced to holding nothing.

They eventually (given time) reach parity

I advise patience, Brother <smile>

Regards, splifingate

Thanks, it took 3 days to sync all photos and data with iCloud Drive when I bought into cloud storage a few months ago, so yes, I need patience AGAIN.

 

[splifingate]

I can appreciate being subtle, and I do reach my TMI moments, but I sure would love for the OS to give me a little more clues as to what's going-on with certain things.

It all ain't perfect--and I should never be an apologist--but some Things are just the way they are...I would advise to /not/ add hypertension to that List