backupgoogle-photossynchronization
I am using Google Photos and quite happy with it, including the option to automatically upload images from both my phone and my camera (via a computer). However, I am uncomfortable with all those precious photos being in just one place which I don't control. So my question is:
It there a possibility to sync the images in both directions, so that I always have a local copy of them all?
You could say that's a kind of reverse backup (perhaps a "backdown", or a "forwardup"?).
You can't sync between accounts. Sync works between an e-mail client on your computer or mobile device and the account on the server (using IMAP). But forwarding or POP fetching can not sync between server accounts.
There is no right combination of settings.
The Google Photos upload checkbox (in the Backup and Sync preferences) is a blanket toggle: it affects all the selected local backup/sync folders. So if you want to backup Drive-only files, you need to leave it unchecked and continue manually uploading your images to the Photos app.
As of yet, the B&S client does not allow fine-grained control of what gets uploaded into Photos. Also for backups, be reminded that Photos has limitations on file types and min/max sizes.
As a workaround for periodic backups to Photos, you can try the following:
For "Removing item", select "Don't remove items everywhere".
Select only the folder(s) you want to back up to Photos
As a side-effect to using B&S, you also retain the images in your Google Drive. But they are linked invisibly to Photos, so:
Best Answer
If you use Google Drive, you can connect the two so that everything in Google Photos is also copied to Google Drive. If you use Google Drive sync, then they'll all be on your hard drive.
In Google Drive settings, check the box next to "Create a Google Photos folder" labeled Automatically put your Google Photos into a folder in My Drive"
Now you'll have a special folder in Google Drive organized by date containing the files from your Google Photos. If you back up locally and/or to the cloud (e.g., Carbonite or Backblaze) you'll be triply protected.
More information from Google Support: How Google Drive works with Google Photos
If you also use Google Drive on your device, you can set that folder to sync to your device. You'll just want to be careful that you don't cause duplicates on your device.