The big reason for using a 5D in house is both it's size compared to a movie camera - you can get in to closer shots. But mainly it has a larger sensor - most movie cameras (film and digital) have a sensor half the size of a 35mm frame so movie lenses are effectively 1.5x as 'long' as you are used to on a SLR camera.
By using a full frame 35mm camera (Canon 5D) the lenses become wider angle than on a movie camera and you get a much smaller depth of field (for the same aperture) which lets you create shots that isolate a persons face in close up.
It's a little surprising that this camera didn't have the APS-C/super35 sensor size used in most movie cameras - that would mean that a lot of standard lenses would work as expected.
The big reason for using a 5D in house is both it's size compared to a movie camera - you can get in to closer shots. But mainly it has a larger sensor - most movie cameras (film and digital) have a sensor half the size of a 35mm frame so movie lenses are effectively 1.5x as 'long' as you are used to on a SLR camera.
By using a full frame 35mm camera (Canon 5D) the lenses become wider angle than on a movie camera and you get a much smaller depth of field (for the same aperture) which lets you create shots that isolate a persons face in close up.
It's a little surprising that this camera didn't have the APS-C/super35 sensor size used in most movie cameras - that would mean that a lot of standard lenses would work as expected.