If you haven't tried Spotlight before, try turning it on:

In Windows 10 (1511) open the settings panel and navigate to Personalization and then Lock screen. Select Windows spotlight in the dropdown for Background. Scroll all the way down and hit Apply.
Now, whenever you see a picture you love, unlock your machine, hit [win]+r on your keyboard and paste the following location:
%userprofile%AppDataLocalPackagesMicrosoft.Windows.ContentDeliveryManager_cw5n1h2txyewyLocalStateAssets
This will open up a folder with a bunch of files, each with a random file name. One of these files is your current lockscreen background. What I generally do is that I type cmd in the location bar of explorer en hit enter, this opens a commandline prompt in the current folder.
Then copy all the files to a temporary location and then rename them to *.jpg in one go:
C:UsersmeAppDataLocalPackagesMicrosoft.Windows.ContentDeliveryManager_cw5n1h2txyewyLocalStateAssets> copy *.* c:tempImages*.jpg
And then you can navigate to that folder, check the image preview in explorer and pick the backgrounds you like. Of most backgrounds you'll find both a portrait and a landscape version.


Jesse Houwing
Jesse is a passionate trainer and coach, helping teams improve their productivity and quality all while trying to keep work fun. He is a Professional Scrum Trainer (PST) through Scrum.org, Microsoft Certified Trainer and GitHub Accredited Trainer. Jesse regularly blogs and you'll find him on StackOverflow, he has received the Microsoft Community Contributor Award three years in a row and has been awarded the Microsoft Most Valuable Professional award since 2015. He loves espresso and dark chocolate, travels a lot and takes photos everywhere he goes.
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