I’m very confused of how should I set physically correct values for the lights that I’m using. If I use manual metering mode with default camera settings it seems like the lux intensity that I put in directional light is physically correct so I can get a lux sunlight chart from the internet and ie. copy the value of 10752 lux into directional light to make it sunny just like the chart says. The problem here is that one unreal tutorial from epic games says that big intensity values that have to be set with manual metering mode may cause lightmass problems.
But then if I use auto exposure histogram metering mode, lighting changes drastically, even tho values are unchanged, and it still uses the same lux units which is very confusing.
So my question, is there any mathematical formula that I can use so I can always set a physically correct light if I want a sunny day or maybe an overcast etc? Or maybe I’m approaching it all wrong? Right now for me it seems like those values have to be eyeballed because that’s what every lighting tutorial does.
And second question, is any of ue4 metering modes the one that is usually used in photorealistic graphics throughout the entire project or does it change heavily?