NVIDIA's latest GeForce Experience beta adds the ability to take screenshots of your games up to a maximum 4K resolution. More, it now sports built-in editing (brightness, contrast, digital vibrancy, and cropping) and Imgur uploading functionality. Happily, both of these functions can be performed in-game via the Share menu accessed by hitting Alt + Z. To get started, you'll need to connect to Imgur via the Share > Connect menus.
The choice of Imgur is a little surprising given the service is known for significant compression, but perhaps something special has been arranged for this partnership with NVIDIA. We've inquired as such, and will update this story should we hear back.
Apart from the screenshot feature additions, GeForce Experience now supports custom streaming overlays (with the option to display viewer count) and custom Twitch servers so you can select the one nearest you for better network performance.
Hit the source if you want further details and instructions, and boot Experience now to download the update which includes the new functions if you haven't already.