OK Now it gets a little tricky. Insert an Image_Map and load your tattoo mask. Also insert 3 math functions. This may seem silly, but you'll see why this is a big advantage later.

Connect the first to your U_Scale and V_Scale. This will control your overall tattoo scale. I adjusted the value to 8% of the original size.

Set U_Offset = 1 and connect to the second math function. This is your horizontal position. I used .21 to move my butterfly over the right buttock.

Set V_Offset = 1 and connect to the third math function. This is your vertical position. I used .26 to move it to the hip.

Set the Image_Mapped = None so the mask does not repeat.

Set the Background = BLACK so the rest of the mask is black.

Connect the mask to the Blender:Blending input. Put a dark color in Input_2 of the Blender. Render. You should see the tattoo mask on your figure. For monochrome tattoos, this is all you need to do.

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