Repeatedly baking normals gives vastly different results.

I cannot figure out how to bake normals in Blender reliably. I can bake normals and get a near perfect result, and then bake them again without changing any settings as far as I can tell, and get something horrendous and unusable.

I baked this normal map from HP to LP without using a cage:

Without changing anything that I’m aware of, I hit bake again, and immediately get this instead:

Obviously something is different, but it’s not anything I’m consciously changing. I’m baking using Cycles. I have the image texture active on the material, but it isn’t plugged into anything, so I don’t see how the normal map already existing could affect subsequent bakes. I just don’t get it, and it’s driving me nuts.

Normal maps should be baked in tangent space. It looks like the second normal map was baked in object space rather than tangent space.

Rekov while I’m doing a combined bake I also have something changing. It’s as if the normals are flipping on me without any input on my part. And, it’s a bake very similar to about eight I have done with no problems in the past. In the same version of Blender I might add. Maybe six hours over several days attempting a bake I thought would be routine. Best of luck here.

Rekov for me ‘Load Factory Settings’ did it and not a minute to soon I might add. Damn I was a short walk from a rubber room. Don’t forget to reset your Cuda in User Preferences.

Thanks guys. I was definitely baking in tangent space, but it seems that for whatever reason it decides to bake in object space if there is already a baked normal in the texture file? Who knows…