Shooting during the “Blue Hour” – after sunset, or before sunrise means setting up a tripod for the long exposure times you will need. But, sometimes it’s not possible to set up a tripod; the location may be too crowded, there may be rules against setting up a tripod at your location, or maybe you just forgot to bring it along.
Here is a way to rescue the situation by shooting hand-held at really high ISO, with very little noise.