Even if their "Uploads" album is completely locked down (showing zero photos to non-friends), their "Tagged Photos" album might be partially or fully visible. Why? Because Facebook allows users to control who sees tagged photos in their "Timeline and Tagging" settings. Many users neglect to change this setting from the default, which is often "Public" or "Friends of friends."

While you cannot see private photos, you can maximize what is visible using these techniques:

If a user has set their profile to "Friends Only," you will only see their public profile picture and cover photo.

Facebook allows search engines like Google and Bing to crawl and index public profiles. If a user previously had public photos that they recently restricted, search engine caches might still hold copies of those images.

If you share a mutual connection with the target, you may gain automatic access to a vast catalog of images due to the "Friends of Friends" visibility setting.

If you cannot see their profile, join their spaces. Many people have strict privacy settings for their wall but are extremely active in Public or Closed Groups.

It is not possible to see all the photos of someone on Facebook without being their friend if they have set their account to private.