SceneCapture2D light problem

Hi, I know there are multiple questions regarding this topic but I did not find working solution yet.
The problem is still the captured textures are too dark.

I have a simple BP with camera, Plane and SceneCapture2D component.
In BP I add materials to Plane and capture shots. The whole thing is for use them on UMG, which I found very complicated. I spent days to create a capturer BP, save images to disk, read images to UMG into UI domain materials and show them. It finally works but the lighting/darkness problem is annoying.

I played with Global Illumination and Post Process Blending Weight Values of component, but the main problem is its not an universal solution, for example works good with a simple textured Wood material, but still very dark with a metallic material. If I increase illumination to see the metallic material, my Wood one will be overlighted.
Same result if I just put a directional light to my BP. I also tried set Auto Exposure min value of PostProcessVolumes as others recommended, but it seems uneffective to SceneCapture component.
Other question is where I should spawn my Capturer BP to avoid other lights of scene. I dont want see multiple light reflections on materials. Unfortunately I cant change the materials itself, I have work with them as I get (no unlit/emissive or other changes).
As you see in images, wood and plastic materials looks acceptable, but metallic materials are all dark. (They ARENT black, but very dark).
Any ideas, solutions?