Do you have the quality values on the image nodes set to "None"?  .  The None option for some reason makes the image map very precise, so precise in fact that the map reduces by 1 pixel.

This effectively puts a white edge on your bump maps which contrasts too much with the actual bump map and leaves an odd line where one island joins another.

You can get round this a couple of ways.

1. Set the quality option on the node to "Quality" which blurs it enough to work, but reduces the quality of your image map.

2. Put Padding round the edges of your UV Islands on your bump map, so that the space around your UV Islands is a mid grey instead of white.

I dont know how you are generating your Bump Maps.  I use 3D Coat which helpfully adds the padding automatically, smearing out the edge of the uvislands out to match the color to the specific island.

Hope that helps.

John

 

Fugazi (without the aid of a safety net)

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