To address your comment, and the overall question, here is how I'd automate the whole process.
I'd use the
screencapture command line utility in a Run Shell Script action instead of using the Take Screenshot and Open Images in Preview actions. For more information about the
screencapture command line utility read its manual page.
The example code produces a filename same as the default when using standard keyboard shortcuts while placing it on the Desktop.
screenShot="Screen Shot $(date "+%Y-%m-%d") at $(date "+%H.%M.%S").png"
screencapture -i -P "$screenShot"
cd "$HOME/Desktop" can be any valid location you'd like.
screenShot="Screen Shot $(date "+%Y-%m-%d") at $(date "+%H.%M.%S").png" the
screenShot variable forms the filename to be saved to.
$(date "+%Y-%m-%d") will be e.g.
$(date "+%H.%M.%S") will be e.g
21.23.07 and the filename would then be, e.g.:
Screen Shot 2016-10-07 at 21.23.07.png, just as if you used the default standard keyboard shortcuts.
screencapture -i -P "$screenShot",
screencapture interactively, by selection or window. The control key will cause the screen shot to go to the clipboard. The space key will toggle between mouse selection and window selection modes. The escape key will cancel the interactive screen shot.
-P Open the taken picture in a Preview window.
Note that you can modify the options of the
screencapture command if you want it to behave differently then the example code. Also, if pressing the control key, which places the screen shot on the Clipboard, it will not then be opened in Preview.