On the Mac I am aware of how to do a screen capture, but it creates a 72 DPI image. We need a much higher quality image because it's for printing on a color laser printer. We need to be able to print this out high-quality so it looks good on a 11 x 17 inch paper. Thanks!
Taken from here.
defaults write com.apple.screencapture type pdf killall SystemUIServer
Several other choices besides pdf and default png, see link.
If you run
sudo defaults write /Library/Preferences/com.apple.windowserver.plist DisplayResolutionEnabled -bool true and restart, the Displays preference pane will include settings for HiDPI modes:
You can save a screenshot of an entire website with webkit2png:
brew install webkit2png webkit2png -F http://apple.stackexchange.com/questions/93321
-F only saves a full-size screenshot. webkit2png uses a HiDPI mode when a HiDPI resolution is selected from System Preferences.