I have a city scene with an HDR and some area light inside a building.
Everything looks pretty nice and smooth so far, as you can see below:
But when I add several other area lamps facing up outside, the lights inside the building gets horribly grainy.
Both renders have 600 samples, 2.79 Cycles, here my other render settings:
How can this be possible? :@
ps: maybe it’s important to say that the area lights in the first picture are part of the project, while the ones added in the second are instanced from another project.
Thanks in advance to who may help me!!