Hidden away

This beautiful moth disguised as autumnal leaves was resting in a garden which I was working in this morning.  It had picked the wrong background for actually being hidden! (I just blipped it on my phone, as I did not have my camera with me)
I have looked through  my insect book but have not been able to ID it.  I think it must be a Hawk Moth of some sort.  Please let me know what it is if you know about moths. Many Thanks.