Edge line appear in render result I want to create an environment texture from a cube map, so I create a cube then map the textures like this: 


But inside the cube, where I put the camera, I can see a black line at the edge's position.



After render, this line is visible at final result too.



volvis told me to change mapping mode, but I use Cycles Render, so I can not find where is mapping node setting.
I wager that this is caused by the image mapping. Textures are set to repeat by default, and the dark line looks like the bottom part of the texture bleeding to view. Try changing the image mapping mode to Extend or similar and see if that works for you.