set an ambient light.
Make sure the map is not leaked; it it is, it will be indicated by ***leaked*** on the compiler screen. Leaked maps have horrible lighting.To solve a leak problem, make sure the map is "sealed" and you don't see a hall of mirrors effect.
And.. how 2 do it?Ich bin ein anfaeger in BSP.
Seeing that your map is entirely exposed to the sky, you might want to go with a little sun_light in order to brighten it up a little even though it's nighttime. _ambient might also work.
for sun lightning there is _sun_ambient I think... _ambient is for all light sources on the map.
you could just add a subtle sun source from the direction of the moon
with a low value for _sun_light
Example? 250?
people use 300 for a daylight map, just play with it a little
Probably something like 50 or 60 for a night map.