Thanks Viacheslav and Hannah.
[this will only work for the back wall of your tunnel and layers that are facing directly forward, side walls should already light up convincingly… no? ]
No, the side walls don’t light up convincingly at all. As I said they should be brighter on the opened end of the tunnel (end of tunnel) but they are all the same brightness. There’s no back wall by the way. The end of the tunnel is open and the light there is supposed to be sun light, hence why it needs to get brighter as the camera gets closer to the open end.
Viacheslav, will your new suggestions get me the right effect which is getting from the dark to the brighter side of the tunnel and or have the brighter side of the gradient advances towards us instead of the brightness change of the first suggestions?
by the way, do you guys know the name of the Andrew Kramer tutorial you mentioned? Thanks everybody.