Why does the Singapore A380 have just one window aft of the upstairs rear door vs apparently 4 on the Qantas A380?
It's probably taken from a helicopter, I've seen quite a few other nice pics by spotters in helicopters around Sydney although I've heard it's quite expensive.
All A380s have 5 windows there but if there's a galley or toilet there, the window pane is replaced by a non see through material which is easier to maintain (Although if they reconfigure the aircraft, they can replace it back to a see through window).
To make things slightly more complicated, Qantas like Singapore Airlines only has 1 see through window there. The 3 'blank/covered' windows behind it are coloured to look like a normal window with the 5th window painted white and red to fit into the livery.
You can kind of see it in the following picture. DSC_2345 by JKKW, on Flickr