...the lightmix feature but the night version had a lot of noise and fireflies even after around 8 hours that i let it render (4k ) but i guess i did something wrong...
LightMix is a post processing feature. If you do radical changes, then there will always be noise. It's because corona establishes adaptive sampling and max sample intensity based on initial render state. If you have light that shines just little bit, and increase it's contribution 10 times, it will display at totally different levels than levels corona sampled the light for. So keep in mind LightMix is better suited just for look development, once you find the right looks you will have to adjust actual lights and re-render as long as you want to keep your rendertimes reasonable.
