How to not use lights?

In screenshot one, you can see where the red cube is very blown out.
In screenshot two, its at the very edge of the map and its the correct color.
I’m currently using a directional light at a 90 degree angle to the surface of the objects. This should be good enough for what I want to do, but as you can see in both images the closer to the center of the screen an object is, the more light it receives and the more washed out it becomes.