Okay, so I now know the problem.... Lights dim at night to keep the balance of the lighting. Bethesda sucks, la-de-da-de-da. I installed RLO and enchanced saturation. Apart from the over-sturation, I had my night lights popping, and mostly everything was fine until I noticed one stormy day that the mountains were worse than an an old fashioned film camera negative, and don't even get me started on the clouds...shesh, they were awful, and at one point I was literally running around in the dark at 8 a.m. Seriously, no hyperbole, I could not see a thing at 8 a.m. The reason was because my in-game brightness was set to a few steps above zero, which worked fine until a dark day or rain hit. In truth I installed saturation to pop colour and lights. Lanterns of Skyrim has no radiant effect until you saturate it. So I threw satuation out the window, because the new lighting makes it suck at times, even though it is excellent at other times, and went back to the washed out colours of base SSE. But I want my dark nights, and I want to allow the game to do what it does, and have dark dungeons and vibrant colours. (I know, I'm asking for a miracle here) In all kindness, I think the Bethesda Weather Dynamic is, well, difficult to mod and it's Bethesda being Bethesda. I then tried RLO and ELE, you know, the NOT COMPATIBLE DUO, and unticked the weather.esp...aha, get what I'm getting at. I need ELE to pop the lights and darken the nights, as ELE does not darken the days. This for me meant that dungeons, day-time, and night-time, all with in game brightness set at default, worked for me, expect when in my Hearthstone house in Falkreth, I have to use Magelight..bleah!