One of the new features in Windows 10 1511 is the Windows Spotlight lock screen. If you haven't already seen it you can go to Settings => Personalization and select the Lock Screen tab, in the drop down select Windows Spotlight.
Next time you lock your machine (Windows + L) or have the machine wake up from sleep you'll see a stunning image. I liked some of them so much that I wanted to have them as my desktop wallpaper. I searched in all the settings but I couldn't see an option on how I could do that. After some exploration I found a way to do it so I thought I'd share.
First things first, here is a warning on this! Read this post very carefully as I won't be responsible if things go wrong - you are using this at your own risk. If you are happy to accept all liability please go ahead and read on.
Now that's over with we to navigate to the folder where the lock screen images are, they are located in C:\Users\<username>\AppData\Local\Packages\Microsoft.Windows.ContentDeliveryManager_cw5n1h2txyewy\LocalState\Assets
Note: You need to replace <username> with your actual username.
One way to get there is to open up the Command Prompt and type the following:
cd AppData\Local\Packages\Microsoft.Windows.ContentDeliveryManager_cw5n1h2txyewy\LocalState\Assets
explorer .
You will be presented with a folder with a bunch of files, sort them by size and then copy (not move) all files larger than 150k into another folder - in this case I copy them into a folder called Wallpapers on my Desktop
The assets folder with lock screen images
Wallpapers folder on my desktop with copied files above 150k from Assets folder
All these files are actually just jpg files without an extension, so to add the extension I just use my trusty Command Prompt again and run the following command to rename the images.
Note: Don't forget to swap to the wallpapers folder!
cd Desktop\Wallpapers
ren *. *.jpg
When I look at my Wallpapers folders all the icons have changed to image icons.
Icons now showing images
I then change the View to Extra Large so I can see the images, you may need to do some tidy up as some images are not wallpapers so go head.
All the lock screen that I had copied across
Once you have found the image you like go ahead and change your background by right clicking on the image and select Set as desktop background - or if you like them all then you can have it slide showing via the background tab in Settings =>Personalization settings.
Enjoy! :)