08-07-2010, 02:23 PM
The important thing with all painting, and especially with realistic matte painting, is to know EXACTLY where your light sources are, and what they are doing. You appear to have four in this image - the moon, the light beam, the lantern, and whatever is hanging in the sky off the top of frame.
Each one of these has it's own colour and falloff, and each causes it's own particular set of shadows. At the moment, a lot of shadows are missing, and this is giving an 'underwater' feel to the image (as if the air was bouncing light back to the city, just like water). The 'god rays' also add to this effect.
I would personally reduce the number of light sources to something a bit more manageable, which would have the nice side-effect of making the image a bit more believable as well. How about taking out the light source in the sky (whatever it is). This would leave a bright light beam hanging above your city, and a lantern with a very localised effect. You could leave the moon there for a bit of ambient light, but it would have much effect at the exposure you would need.
Most of your image will then be in shadow, with powerful highlights and glints around the central beam.
Hope that gives you some pointers - look forward to an update.