Post render lighting

I saw this - https://www.blendernation.com/2021/07/01/blender-tutorial-no-16-how-to-create-light-layers-in-blenders-compositor/?utm_source=newsletter-1463&utm_medium=email&utm_campaign=BlenderNation-daily, and thought what the hell, let’s see what I can do with it.

Each of the render passes came in at around 5.5 minutes, and so doing it all in render would take around 23 hours. Instead, I had 16m15s of total render time. Rendering the composite without denoising took around two minutes for the whole anim. Bumped up to 7 seconds or so per frame with denoising turned on. Still, total time less than an hour. Colour me impressed.

I know that the sun should show some travel, but then we are back to 23 hours to pull that off.