I can talk about Reshade too if you want. This raises JUST the dark shadow part a little for more details. change ' CC:Out black' (default at zero) to 0.10. Under ENBEFFECT.FX (this is color correction).
Changes other part for Dawn, Sunrise, Night, etc. Under ENVIROMENT, adjust AmbientLightingIntensityDay (default is 1) to go to 1.1 or 1.2 or higher (small increments only, or it will look weird) Just make sure ILAmount is not zero (I use 3) SSIL is the part that iluminates reflective lights onto objects. You can adjust values in SSAO_SSIL section but write down original values as backup Make sure ' EnableSSAO' is checked in EFFECT section. With ENB menu (hit Shift-Enter to bring up) No need to have 2 features running side by side doing the same thing, just waste your performance. Same effect, adjustable, and more performance friendly. Turn on Ambient Occlusion in ENB instead.
In reality, light bounces everywhere, so we can tell it is day time without looking at direct sun light. Your problem: there is not enough bounce light. Best if you get the latest version from ENB website. This is a fundamental problem with game's original ambient occlusion feature (game uses HBAO+ I think) without options for us to adjust.This can be remiedied by using ENB settings.