iCloud iCloud Photos - iMac, iPad, iPhone - what library is the master?

[icloudy]

Hi,
My wife has an iMac (2015 Big Sur 3TB Fusion drive) which holds all her photographs.
The library of photos on this iMac has grown over years from when she began using iPhoto on a G4 iMac to the Photos app she now uses.
So she has photos on her iMac that she doesn't have anywhere else and DOES NOT want to share.
The iMac is in effect her Master device and she wants this to be the master hub for ALL her photos.
We have a time machine backup on the iMac so we do have a local backup of her photos incase the HD dies.
However she also has an iPhone and an iPad both of which she uses to take photos.
Is it possible to use iCloud to share/sync the photographs on these devices to her iMac automatically, without sharing her iMac library to the cloud too?
So for example can I use iCloud to share/sync every photo on her iPhone to automatically appear in the photos app on her iMac, but not have the photos of her iMac show on the iPhone and iPad?
If she accidentally synced her iMac photo library to iCloud, can I safely delete these by logging into iCloud.com without then losing them from the iMac too?
Do the originals still stay on the devices when synced to iCloud?
So if I deleted the entire photo library from iCloud and then re-synced just the iPad and iPhone to iCloud, would this re-upload all the photos from those devices to iCloud or would they have been deleted from the devices when I deleted the library from iCloud?
It get's hard to keep track of what's what when iCloud get's involved. All she really wants is for the iMac images to only be available to the iMac and for the photos on her other Apple devices to automatically transfer to the iMac.
Hope that makes sense, any clarification on the best way to achieve this would be appreciated.
Thanks

 

[Arctic Moose]

If you connect to iCloud then iCloud will be the master, so what you’re proposing is dangerous.

What you can do is just leave the old photos in the library they’re in and create a new library, and use that to sync new photos.

(You can choose which to use by holding down option when starting Photos.)

 

[icloudy]

If you connect to iCloud then iCloud will be the master, so what you’re proposing is dangerous.

What you can do is just leave the old photos in the library they’re in and create a new library, and use that to sync new photos.

(You can choose which to use by holding down option when starting Photos.)

Thanks for the reply.
So does that mean there's no way to sync the photos from the iPad and iPhone to the iMac without the iMac's photos also syncing?
Also can you clarify what happens when synced photographs are removed from iCloud.com.
For example if I take a photograph with the iPhone which is synced to iCloud and then delete the photo from the photos folder in iCloud.com, does that photo still remain on the iPhone or would that be deleted from the phone too now it's synced to iCloud?

 

[hg.wells]

Thanks for the reply.
So does that mean there's no way to sync the photos from the iPad and iPhone to the iMac without the iMac's photos also syncing?
Also can you clarify what happens when synced photographs are removed from iCloud.com.
For example if I take a photograph with the iPhone which is synced to iCloud and then delete the photo from the photos folder in iCloud.com, does that photo still remain on the iPhone or would that be deleted from the phone too now it's synced to iCloud and iCloud is the master?

Correct, the whole idea of iCloud is that everything is in sync and accessible on all devices.

Deleting a photo from any device or iCloud.com would then remove the photo from all devices.

 

[icloudy]

Correct, the whole idea of iCloud is that everything is in sync and accessible on all devices.

Deleting a photo from any device or iCloud.com would then remove the photo from all devices.

Okay, so if I turn iCloud sync off on my iPad and iPhone, could I then delete the previously synced photographs from these devices from my photos folder in my iCloud.com account without them then disappearing from the devices themselves?

I assume that the images I have on the iPhone and iPad would remain on them because I have removed them from iCloud's control once it is no longer synced, is this correct?

I think what I'm trying to do is better control what goes up to iCloud and what doesn't.

I'd rather have it so the iMac does not automatically receive photos taken on the iPhone and iPad, than for the iMacs library be shared on iCloud too (it's too big).

Hope that makes sense.

 

[hg.wells]

Ok so let’s start from beginning, what is your end goal, what would you like your setup to look like?

If you turn iCloud off on all those devices, they are not going to be backed up unless you are syncing them. Which is one of the reasons why iCloud is great, I take a picture on all my devices and it’s everywhere and I don’t need to worry about it.

If you did turn off iCloud on those devices, you would then have to import those into the photo library on your Mac manually, which would them push those to iCloud. But then you also said you didn’t want the Mac uploading to iCloud because the library was to large.

Whatever you decide should ideally be as simple as possible and it sounds like you maybe over complicating things.

You mention your library is big, how big are we talking? A large music collection to me could be thousands of albums, but to you could be 20 albums.

 

[Arctic Moose]

So does that mean there's no way to sync the photos from the iPad and iPhone to the iMac without the iMac's photos also syncing?

There is, just create a new library on the Mac to use for iCloud.

Also can you clarify what happens when synced photographs are removed from iCloud.com.
For example if I take a photograph with the iPhone which is synced to iCloud and then delete the photo from the photos folder in iCloud.com, does that photo still remain on the iPhone or would that be deleted from the phone too now it's synced to iCloud?

As I said, iCloud is the master. Deleting a photo anywhere will delete it everywhere.

You could use photo stream instead, but if you have HEIF on your phone this will sync inferior photo files to the Mac. The last option is to connect the phone and iPad to the Mac with a lightning cable and import the files into the Mac library.