Lighttable                     <a>
This  button switches the light table
mode  on  and off.  Once this mode is
activated  you  can  see not only the
current    screen    but   also   the
background  buffer  behind  it  at  a
lower  intensity.   You  may  work as
usual   effecting  only  the  current
screen.  Switching off the lighttable
mode  you  will  once  again  see the
current  screen  in  full saturation.
When  using  the  zoom  function  the
light table mode is not available and
cannot  be  activated,  turn the zoom
mode  off and then reselect the light
table mode.