Hi Melanie,
There really is no standard when it comes to bitrates. With H.264 can get away with lower rates. BluRay, for example, is usually around 40Mb/s (H.264), so that’s a good reference point for “Hollywood” HD quality. If you have a lot of noise in your movie, then it will require a higher bit rate or you will start seeing artifacts. Lots of motion, rushes, shaky cameras all require more data to look good since compression depends on changing pixels from frame to frame. Raise the brightness on your monitor and look at your backgrounds/dark areas, that’s usually where artifacts will pop up.
Prores varies between 70 and 150 Mb/s depending on the format you pick, you won’t have control over the bit rate.
Vince Becquiot
Indigo Live | Kaptis Media
San Francisco Bay Area