IDL shows inverted images after use of DEFROI

In case that the display of images is inverted every time you show it, it is very likely
that one system variable was changed.
Please try to set

IDL>device, set_graphics_function=3


This happens most likely if you type CTRL-C within the program DEFROI

vmware stops ctrl and shift key from working

If you encounter that vmware stops ctrl and shift keys from working in linux then do not panic!

The solution is to run setxkbmap in a shell.
This command brings back the shift and ctrl keys.