RedMew/map_gen/day_night_cycles

In terms of daylight during the day/night cycle:

when dusk begins the light decreases until evening (aka nighttime) which is full darkness until morning which increases the light level until dawn (aka daytime) which is full brightness until dusk

Defaults as follows: ticks_per_day=25000 (approx 6 mins 56.4 secs) dusk=0.25, evening=0.45, morning=0.55, dawn=0.75

If you keep your numbers < 1 , it's the percentage of the total ticks at which the phase of day will change Not sure what happens if you go > 1

When setting these variables, the command will fail if it changes the order of the phases. Ex: morning must be > evening but < dawn

Lastly, the map starts at time tick 0 so if you want to start during full daylight you want a dusk > 0