This bug affects Linux & Windows
You can even duplicated it in the start scene
1. Change all the camera settings (Exposure, gamma etc)
2. Render
3. Split the screen and go to a 3d view
4. Press 0 to go to cam view
5. Press Ctrl+Z for preview
The image from preview and Octane Standalone (If you ORBX export your scene) are the same (btw Orbx does not export the resolution setting)
The image from F12 render ignores some settings (I think gamma and saturation)