I'm trying to make dynamic sunrises and sunsets in my game but I have some problems. My scene is surrounded by mountains and when the sun tint is still hot the sun is not visible but, the trees that are far from the player (Around 100 meters) are lighted like if the mountains are not casting shadows, and when I get closer to theses trees they become black as they should be. If I extend the shadows distance it changes nothing. Also, when the sunrise, even if it should not be visible it should do some ambient lighting, but everything is totally black except some trees.
I would look at perhaps the shader materials, Light distance in shader.
PeerPlay has great tutorials on shaders https://www.youtube.com/watch?v=t8qBCltSqV4
Alternately the asset store might have something fun. https://assetstore.unity.com/packages/vfx/shaders/free-skybox-extended-shader-107400