Spikelite provides the following assistance for this interested in quality snaps.
Getting 4k ScreenShots/Video from a 1080p screen:
Requirement: Nvida GFX card, 1070+ recommended
Step 0: Make sure your system and drivers are up to date
Step 1: Right click your desktop and open “NVIDIA Control Panel”
Step 2: From the left side navigation pane, under “3D Settings”, select “Manage 3D settings”
Step 3: In the Global Settings tab, set your “DSR - Factors” to 4.00x and “DSR - Smoothness” to 0%, then apply
Step 4: In the “Display” section of the left side navigation pane, select “Change resolution”
Step 5: Select the Display that you will be running the game on, and then select the highest resolution listed under the “Dynamic Super Resolution” section of the “Resolution” pane towards the middle bottom of the window. It may be something similar to 1080p, 3840 x 2160, HD (4.00x)
Step 6: Launch your game
Step 7: In the control panel of the game, set the resolution of the game to the new high resolution option which is available, from our examples this will be 3840 x 2160
To undo the above:
Step 1: Right click your desktop and open “NVIDIA Control Panel”
Step 2: In the “Display” section of the left side navigation pane, select “Change resolution”
Step 3: Select the Display that you will be running the game on, and then select the highest resolution listed under the “Ultra HD, HD, SD” section of the “Resolution” pane towards the middle bottom of the window. It may be something similar to 1080p, 1920 x 1080 (native)
Your games should automagically revert to using this. If they dont, you will have to change them in the control panel for the game in question.
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Some notes about that process, it will jack up your desktop on that screen. If you have multi-display, this will jack that up a little too. Some windows and other icons outside of the game will get jacked up. Its a bit janky, but it works for taking the screen shots, I wouldn’t be using this all the time.