That is an excellent question and I have a very easy answer…
Zbrush Normal Map Generation Sucks!
I have literally been fighting how it generates Normal Maps for the last 2-3 weeks. So, I finally gave up and went to the all and powerful Google to get some answers. Turns out that most people agree with me and their answer is to use xNormal. Okay… sure. Another application to add to the pipeline. Why not?
Therefore, I went to see what they would look like with a quick test. Needless to say, not only was the map generation faster, but it was much more accurate with none of the “bad things” that were happening in Zbrush.
The only problem I’m having now, is when I import multiple objects for batch processing, xNormal isn’t analyzing individual objects its treating it like it is one object. So, there’s overlapping normals. For example, instead of the normal just showing the skirt, it is also showing the scabbard and the harness and buckle on top of the normal for the skirt. In other words, I’ll either have to use FBX as suggested on EAT3D.com or I’ll have to do one by one and then piece them together in Photoshop. Needless to say, no fun to be had.
On top of that, I’m currently travelling to Philadelphia for the day job and my capability to work will be very limited, but I will still try to figure it out while in Philly.
I think that’s all for now.