thanks ! yeah I ve been inspired by the way top 2D artists do their grayscale value before coloring process. Also it help to flesh out the mood of the render fairly easy without being distracted too much from texture and reflection stuff.
also it's easier to spot any "bug" in the model too .
anyways, here 's the final render with completed material , all done in UE4 and render using Nvidia Ansel + Ray Tracing .
Full project on my Artstation : https://www.artstation.com/artwork/9mKEEL
Turn Table
some WIP concepts :
wireframe