How to make black parts not grainy while shooting video?

I've got a Nikon D7000.In the movies, during dark scenes the dark parts are black, but when I shoot a video with my camera, the dark parts are grainy and noisy. Now, I know that they use high end cameras in the movies but isn't there a way to avoid this?

The grain is usually be cuase your camera is trying to digitally adjust the exposer. For DSLRs, I think you'd need to keep your ISO low and/or keep your exposer gain low or nuteral as well.

Also, you can try getting a faster lense like 1.8 instead of the stardard stock kit lense.

What the guy said above/below me is right but you can also get a software called denoiser or something like that i'm not quite sure what it is called but it works miracles and i "quote" well not really i don't…