I don’t know if I am doing something wrong here but this always always seems to occur to me when I bring a model in from Maya, sculpt it and then send it back to Maya along with either a normal map or to a lesser extent with a displacement map. Doesn’t seem to matter if I use GoZ or the simple OBJ import and export functions.
For example, I bring in a simple low res sphere. Subdivide it say 7 or 8 times to get up to a million poly’s and then use one of the canned brushes to sculpt. Doesn’t matter which one I used. I then create my normal map and apply it in the bump channel in Maya. The changes I made (for example with the Stitch 1 brush make a simple row of stitching down one side and nothing else) show up nicely however everywhere else on the model where I didn’t make changes, never even touched with the brush also has artifacting rendered. Its like noise has been introduced or something and for the life of me I don’t know how.
The normal map itself in photoshop doesn’t show any noise in those areas but obviously something is being introduced.
Does this sound at all familiar? I’ll try and post up some examples tonight when I get home.