The aurumn map version just looks impressive, way better than these shots I chose, especially the colours of the ground/fields and the trees-awesome!
I only wonder why my 4.09 Histo mod install shows much less bright daytimes in the autumn mission I built.
In 4.101, 16.00 seems to be the usual IL-2 16.00 e.g., in 4.09m, 15.00-16.00 is very darkish, a dusk ambient, 17.00 is almost night.
You might take a look at the landlight.mat file included in the install. It is in the autumn textures file and it influences various parameters of light and contrast and such things. I changed the normal default settings of 1.0 for each parameter, to those I thought looked good - on my install. Try changing the parameters around and you might get a result that you like a better.
There is also always the option of changing the texture files in a graphics editor. It is is not as difficult as you might think. Should you wish to try it out, I would suggest increasing the brightness slightly while increasing contrast much less, or leaving it as is. I use Paint Shop Pro7, as good a program as there is even though more than 10 years old, and the brightness setting would be something like 3 and the contrast 1 or 0. You won't see much difference directly, but the game will ... you can also use the command twice or three times on each texture as well ... but don't overdo it. And of course apply the same to all the textures ... otherwise they will start to contrast with each other.
Also, should you wish to try this out, backup the old textures first.
And also, there is a big difference internally how the game renders colors. 4.09 is far less sophisticated than 4.101 and cannot do the lighting as well as 4.101. In 4.101 you can see differences in lighting and coloring when you change the mission starting time by as little as 30mins. 4.09 cannot do that ...
That alone is the reason why I wholeheartedly embraced 4.101 when it first came out and I discovered the color/light rendering improvement.