Backdrop at Mason Park Bridge

[Sumpter250]

I am also noticing that my 3D trees are very dark. May have to get some lighter green spray paint and mist them.

Looking at the first "real tree" photo, and the layout photo above it, your 3D trees aren't all that much too dark.
Your background trees could probably use darker, close to the foreground and fade to misted over. In the real trees there's a sharper distinction between the green, and the shaded/shadowed foliage, as the distance increases, the distinction blurs, and the overall color gets "lighter".
I really like the process you are using to create the backdrop scene.