- Open developer tools.
- Activate the device toolbar.
- Set the DPR to 3 and make sure the screen is the width you want to capture.
- Press cmd/ctrl-shift-P to bring up the command popup
- Type 'screeenshot' and select one of the screenshot options - area, fullsize, node, or just plain screenshot to capture the viewport.
Result: high res capture of your webpage.
To get the 'dramatic' look from this tool, load it into powerpoint, apply a 3D transformation, overlay a radial gradient to get a vignette kind of look, then just do another screencapture.