I've made big cube and problem solve but better will be use sky with cube flag but I can't make them bigger. In manual is that size of sky cube depends of camera.clip_far but this way not working.
BTW best way will be if I will be able to use something like backgroud image to simulate cosmic space with milions of stars.
But... I've made a huuuuuuge passable cube with flipped normals and it's ok
