help required.

[Knight-Templar]

I am using Cinema 4D, to creat models, such as space ships, cars etc. I would like to put these into scenes. Ie a space ship flying through space or going towards a planet.
My problem is not matter how i try to incorporate the space ship into a space scene which has been made in photoshop the ship just looks as if it has been placed there.
Is there any tutorials out there that people would like to share, which i could follow to make the scenes more realistic.

Simon