So here's what I found...
I'm guessing there is a limit to the pixel size of a Background image... I reduced the size and was able to insert it.
It DOES work with the Physical Rendering settings, you just have to disable the SKY.
There was NO GRADIENT to start... I still don't know where the blue color is coming from.. but with the photo background, I'll be able to "cover it up"...
I am trying to accomplish a DUSK setting, but difficult to get ENOUGH ambient light without distracting shadows coming from a "low sun"... I may try to use a heavy cloud cover or some other ATMOSPHERE setting to help..
Unfortunately it's a CHANGE ONE THING / RENDER deal... which takes a long time... Even with PARTIAL RENDERING...
Duane
Visual Frontiers
AC25 :|: AC26 :|: AC27
:|: Enscape3.4:|:TwinMotion
DellXPS 4.7ghz i7:|: 8gb GPU 1070ti / Alienware M18 Laptop