First, make sure the NIGHT is selected on the SCENE dial.
Long-press the SET button to access Night Glow for Color, Green, Grey.
Turn off EIS.
Photo Mode: Try the Auto Shutter setting. For finer adjusts, try 1/15 sec or 1/24 sec. Adjust the Gain plus or minus from 0 to see what works best.
Video Mode: Try 24 fps or 30 fps at 720p. Adjust the Gain plus or minus from 0 to see what works best.