I’ve opened a complex scene in Maya for render and for being able to see the cameras better, I’ve scaled them by 10. There are three cameras in the scene. And when it came to render from a camera with a close foreshortening to objects, mental ray could not complete visualization because of the many warnings like
warn 542003: suspect illegal geometry truncating, modify clipping plane
I’ve reverted a scale to 1.0 and solved a render problem.