Please see ambient light scenario compared to real photo. Octane completely ignore indirect light bounce to polygons that are not directly exposed to ambient sky. I have the same colors and the same ground brightness as in real photo.
There is no light bounce to ceiling from floor and adjected walls.
It even partially ignore reflections :
Please don't tell me that this is physically accurate.
To make the same brightness in Octane there is need to increase ground brightness but in real scene ground isn't that bright - there is more grass around than pavement. Also there is need to fully increase diffuse roughness that works only for Diffuse material ( problem described here : viewtopic.php?f=23&t=80314&p=414925#p414925 )
Increasing sky brightness do nothing for polygons oriented directly to ground. There is no light bounced from walls to them - only from ground that is very strange...
more references : https://www.shutterstock.com/pl/search/ ... chitecture