Otra opción es usar screencapture:
screencapture -oic
-o desactiva las sombras, -i captura de un área, y -c copia la imagen al portapapeles.
Este sería el uso de un temporizador de 5 segundos y guardar la imagen en un archivo:
screencapture -oi -T5 /tmp/screencapture.png
Ejecutar screencapture -h a lista de todas las opciones:
$ screencapture -h
screencapture: illegal option -- h
usage: screencapture [-icMPmwsWxSCUtoa] [files]
-c force screen capture to go to the clipboard
-C capture the cursor as well as the screen. only in non-interactive modes
-d display errors to the user graphically
-i capture screen interactively, by selection or window
control key - causes screen shot to go to clipboard
space key - toggle between mouse selection and
window selection modes
escape key - cancels interactive screen shot
-m only capture the main monitor, undefined if -i is set
-M screen capture output will go to a new Mail message
-o in window capture mode, do not capture the shadow of the window
-P screen capture output will open in Preview
-s only allow mouse selection mode
-S in window capture mode, capture the screen not the window
-t<format> image format to create, default is png (other options include pdf, jpg, tiff and other formats)
-T<seconds> Take the picture after a delay of <seconds>, default is 5
-w only allow window selection mode
-W start interaction in window selection mode
-x do not play sounds
-a do not include windows attached to selected windows
-r do not add dpi meta data to image
-l<windowid> capture this windowsid
-R<x,y,w,h> capture screen rect
files where to save the screen capture, 1 file per screen
También puede utilizar toggle-osx-sombras para desactivar las sombras por todas partes en OS X:
git clone https://github.com/pufuwozu/toggle-osx-shadows.git;cd toggle-osx-shadows;make;mv toggle-osx-shadows /usr/local/bin;toggle-osx-shadows
