Cameras which can take up longer filmreels as standard 30ft/15m cartridge - are required by professionals. This was the old Kodak Ektasound 200ft/60m cartridge which is not available anymore and the rare SD8 magazines for few Beaulieus. From 2005 until 2006 available was the SUPERMAG 400 filmmagazine which can be loaded by yourself with a special daylightcartridge with filmreel inside. This magazin has its own electricdrive/electronic and powersupply. Fits easy in appropriate sound cameras which are made for the old Kodak Ektasound 200ft/60m cartridge.
Here is the list of cameras: