Below we will see how you can take a snapshot or screenshot of the screen locking of Windows 10.
Since Windows 8 there is this feature, which displays a separate lock screen. When the computer you are locked, a full-screen image is displayed instead of the login screen. It is an additional screen that appears with a background and some useful information, such as the clock and date. Appears before you can select a user account to log in. 
Post Windows 10, Microsoft added the Spotlight feature. Spotlight is a feature that allows you to have a random image on your lock screen every time you open it computer you.
If you like one of these images and want to get a screenshot of the lock screen in Windows 10, follow these steps.
Before proceeding, make sure you are signed in to your Windows 10 account. Windows 10 comes with two lock screens. The first one appears when you are logged in to the user account and your account is locked. The second appears when you log out of the user account. It is called "default lock screen” and appears automatically when your computer is idle for a certain period of time.
To capture the personalized lock screen, once you log in to the user account, lock your computer and do the following:
Press Win + L together to lock your computer. The lock screen will appear.
Press the PrtSc / SysRq button on your keyboard.
Press the Enter key to close the lock screen and log in to your account.
Open Paint and paste the screenshot from the clipboard.
Are you ready. The screenshot of the lock screen will be pasted from the clipboard.
