ghostship2 posted at 8:27 PM Sat, 9 November 2024 - #4491196

Normal maps and bump maps serve the same purpose so use one or the other but not both at the same time. Also, Im guessing you are rendering in Cycles? Cycles converts bump maps into normal maps. Some have said there are problems with normal maps in Poser and I would tend to agree because I've had issues with them myself. IIRC you are supposed to set them at a strength of 1.0. This ALWAYS results in way too much bump in the texture. Also keep in mind if you are using PBSDF for your textures that it's roughness is modulated by the bump maps/normal maps. That means the bumpier the map, the rougher/less shiny your object will be.

I'm not an expert but let me take a stab at this.

I think you can reduce the strength by plugging your normal map into the cycles NormalMap node, that allows you to adjust the Strength. (If you're starting with a height map, and not a normal map, you would use the Bump node and it also has a Strength adjustment. NormalMap is if you already have a normal map as your image and want to alter it.)

With a height map (i.e., the input to Bump or Displacement), the brightness of each pixel indicates how high that point should stick out. For displacement it actually sticks out, for bump it basically figures out the angle the surface would be at if the point was actually raised by that much (but doesn't actually raise it). So, if you lower the strength on that bump or normal, it just makes it stick out less. Easy.

With a normal map, the color of each pixel encodes what direction the surface at that point should be facing. If you just lower those values, I think it's going to end up changing the direction they face, which is not necessarily the same as making them closer to parallel with the object surface (which is what lowering the height would do). So, yeah, leaving the strength as 1 makes sense.

Changing the direction the surface is pointing will change the direction light is reflected from that point. That could deflect light away from the camera so the point looks darker.