They have gone from way to dark to way to bright it seems. But other areas still look to dark. Lighting is just really strange in TSW, TSW2 and TSW3 and im not even talking about the bugs like the sun shining through the solid roof of the locos.
Entering a tunnel it should be very dark. Dark like looking into a bottomless hole or pit. And when you enter you should not be able to see anything in the tunnel itself. You should still be able to see stuff in your cab (assuming lights are turned on of course). Then as your eyes adjust... or in DTG terms... your eyes are adapting to the darkness then it should gradually become brighter as your eyes take in more light and allows you to see in the dark. And when exiting the tunnel you would be near blinded by brightness for a moment until your eyes, again, adapt to the light by taking in less light and allowing you to see better in the light. The way DTG has implemented this it looks like their eye adaption is using the same exact procedure when ENTERING a tunnel as it does when EXITING a tunnel. That is; it creates a bright flash (henceforth called the flashbang effect) when you enter which it absolutely shouldn't. The flashbang effect should only happen upon exiting the tunnel (or any other dark or poorly illuminated area) and entering a brighter one. It's almost like their ENTER effect has it's values inverted. So instead of MINUS to brightness effect when entering a tunnel or dark area they are using the same copy-paste PLUS brightness effect as seen when exiting tunnel/dark area. They should just invert their numbers for the entering part of it and boom... fixed. (yeah, yeah, I know it isn't that simple, but it 100% looks like their enter dark area is same exact code as exit dark area).
That "flashbang" as you call it is NOT part of eye adaptation. It's caused by the transition from the world lighting to the baked lighting in the tunnels.
